I've just clicked and the forum did load fine. Maybe it's a temporary thing from your side (ISP or something).Sadly, the thread starter suddenly went silent, so this thread here doesn't really have an outcome. Maybe things get better over at Feelthere's, that's why I repeated the dev's suggestion.

Okay, thank you! I'll try again there soon.

When I have problems with any thing in the aircraft, I use ADDIT PRO. There you can put in another cockpit. Or it will tell you whats wrong with the .cfg :(

This is a shot in the dark and I hope I am not repeating anyones suggestions as I didn't read the entire thread. Maybe when you had uninstalled it before I assume, the gauge entries stayed in the FSX config file, therefore when you went to reinstall it, FSX did not activate the gauges as if you installed it for the first time. If this is the case, open your FSX configuration file and find the entries for this aircraft and remove only the lines for the associated gauges. Then restart FSX, and when you go to select the the Citation, it should ask you to verify and accept the gauges. if you aren't comfortable doing this, remove the FSX config and let it rebuild. The only downside is unless you backed up your tweak entries and gauge entries except the Citation, you will have to go through verifying the gauges for all of you add on aircraft from scratch. Hope this helps.Warm regards, Jeff