Rules and items that begin with a number

I made a few attempts at creating a rule, but never succeeded.

I use the offical release of openhab 2.0
I have a samba share to my config files (ubuntu)
I connect (from a Windows Machine) with the user “openhab” to this share and made *.rules file

Now i use Eclipse SmartHome Designer to make/edit my rules

I have some questions about the syntax:

My items or channels begin with a number of the floor of my home (i.e. 2ESslaapkamer_Switch)

Designer show the message:

X mismatched character 'S' expecting set '0'..'9

I also have a channel i.e. kodi:kodi:740d21d3:control

can i use : in a rule?

shold all red crosses be absent in the designer in order for the rule to work??