Hi Guys (@mstormi / @rossko57)
after a weekend with testing, stripping of my setup to nearly virginity 
, and try to understand the logging errors, when i found the words lambda and createTimer after setting the log:
I, then stopped all my rules and worked on workaround for them. I understand that my rules are fired multiple times within a second, so that the timer comes to an error. But as rossko said
was a stimulation to me and i have stay tuned.
While doing my tests …, i found this post https://community.openhab.org/t/rule-received-command-or-received-update/35030/3 from @ThomDietrich which points me in the right direction. It was my mania to secure all and everything, i looked into my mapdb and there i found the reasons.
With a good level of OH 2.3, i changed now to OH 2.4-M. Although there are still some warnings
2018-10-12 13:09:55.610 [WARN ] [org.eclipse.jetty.server.HttpChannel] - /rest/sitemaps/events/subscribe
2018-10-12 13:40:54.446 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'voltage' in thing 'avmfritz:FRITZ_DECT_210:Fritz-Box-7490:116570136076' does not exist, recreating thing.
2018-10-12 13:40:54.500 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'voltage' in thing 'avmfritz:FRITZ_DECT_200:Fritz-Box-7490:087610467933' does not exist, recreating thing.
2018-10-12 13:40:54.561 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'voltage' in thing 'avmfritz:FRITZ_DECT_210:Fritz-Box-7490:116570075282' does not exist, recreating thing.
2018-10-12 13:40:54.619 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'voltage' in thing 'avmfritz:FRITZ_DECT_200:Fritz-Box-7490:087610494097' does not exist, recreating thing.
2018-10-12 13:40:54.686 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'battery_level' in thing 'avmfritz:Comet_DECT:Fritz-Box-7490:119601003400' does not exist, recreating thing.
2018-10-12 13:40:54.781 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'battery_level' in thing 'avmfritz:Comet_DECT:Fritz-Box-7490:119600949320' does not exist, recreating thing.
2018-10-12 13:40:54.869 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'battery_level' in thing 'avmfritz:FRITZ_DECT_301:Fritz-Box-7490:099950077350' does not exist, recreating thing.
2018-10-12 13:40:54.919 [WARN ] [al.handler.AVMFritzBaseBridgeHandler] - Channel 'battery_level' in thing 'avmfritz:FRITZ_DECT_301:Fritz-Box-7490:099950074210' does not exist, recreating thing.
2018-10-12 13:40:55.337 [WARN ] [e.jetty.util.thread.ThreadPoolBudget] - Low configured threads: (max=8 - required=1)=7 < warnAt=8 for QueuedThreadPool[ServletModel-11]@12563c{STARTING,8<=0<=8,i=0,q=0}[ReservedThreadExecutor@1712906{s=0/1,p=0}]
I think that @cweitkamp looks for a solution, and of cours you, Markus (https://community.openhab.org/t/low-configured-threads-warning/52084).
Also there seems to be a problem with the ios-app and OH.
2018-10-07 01:26:27.418 [WARN ] [eclipse.jetty.servlet.ServletHandler] - /proxy
java.lang.NullPointerException: null
at java.net.URI$Parser.parse(URI.java:3042) [?:?]
at java.net.URI.<init>(URI.java:588) [?:?]
at java.net.URI.create(URI.java:850) [?:?]
at org.eclipse.smarthome.ui.internal.proxy.ProxyServletService.uriFromRequest(ProxyServletService.java:282) [147:org.eclipse.smarthome.ui:0.10.0.oh230]
at org.eclipse.smarthome.ui.internal.proxy.AsyncProxyServlet.rewriteTarget(AsyncProxyServlet.java:66) [147:org.eclipse.smarthome.ui:0.10.0.oh230]
at org.eclipse.jetty.proxy.ProxyServlet.service(ProxyServlet.java:63) [80:org.eclipse.jetty.proxy:9.3.21.v20170918]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [31:javax.servlet-api:3.1.0]
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:848) [85:org.eclipse.jetty.servlet:9.3.21.v20170918]
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:584) [85:org.eclipse.jetty.servlet:9.3.21.v20170918]
at org.ops4j.pax.web.service.jetty.internal.HttpServiceServletHandler.doHandle(HttpServiceServletHandler.java:71) [183:org.ops4j.pax.web.pax-web-jetty:6.0.9]
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548) [82:org.eclipse.jetty.security:9.3.21.v20170918]
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1180) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.ops4j.pax.web.service.jetty.internal.HttpServiceContext.doHandle(HttpServiceContext.java:284) [183:org.ops4j.pax.web.pax-web-jetty:6.0.9]
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:512) [85:org.eclipse.jetty.servlet:9.3.21.v20170918]
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1112) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.ops4j.pax.web.service.jetty.internal.JettyServerHandlerCollection.handle(JettyServerHandlerCollection.java:80) [183:org.ops4j.pax.web.pax-web-jetty:6.0.9]
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.Server.handle(Server.java:534) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:333) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:251) [84:org.eclipse.jetty.server:9.3.21.v20170918]
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:283) [76:org.eclipse.jetty.io:9.3.21.v20170918]
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:108) [76:org.eclipse.jetty.io:9.3.21.v20170918]
at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) [76:org.eclipse.jetty.io:9.3.21.v20170918]
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.executeProduceConsume(ExecuteProduceConsume.java:303) [87:org.eclipse.jetty.util:9.3.21.v20170918]
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceConsume(ExecuteProduceConsume.java:148) [87:org.eclipse.jetty.util:9.3.21.v20170918]
at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:136) [87:org.eclipse.jetty.util:9.3.21.v20170918]
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:671) [87:org.eclipse.jetty.util:9.3.21.v20170918]
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:589) [87:org.eclipse.jetty.util:9.3.21.v20170918]
at java.lang.Thread.run(Thread.java:748) [?:?]
2018-10-07 01:26:27.459 [WARN ] [eclipse.jetty.servlet.ServletHandler] - /proxy
java.lang.NullPointerException: null
One more time, thanks a lot for your help.