1) There`s an error message appearing (see attached jpeg file below) everytime I run FSX.
Known FSX problem, which has been discussed several times, just ALLOW the module to run, regardless of what FSX thinks, don't worry if it doesn't work the first time, then exit FSX and launch it again. The error usually goes away. If not, reboot and try again.
2) GoFlight module doesn`t work anymore
Sorry, don't know anything about this. Do they have some a module that is added to the EXE.XML file, OR the DLL.XML file ? In this case, it would be useful to have a look at the content of your EXE_XML_Before_Addon_Manager and DL_XML_Before_Addon_Manager files.
Both are located into %APPDATA%\Microsoft\FSX
Send me the files via email. Don't copy and paste, but ATTACH the files to the message.
3) Key2Mouse breaks down- and has to be reinstalled
Please, be more specific. Does it work after reinstalled, or not ? Are you on Vista ?