Been reinstalling a lot of stuff and noticed that you have been making loads of callsigns............thank god for that!

There have been a few errors, not in the callsigns, but in how they are made/designated/listed. Whilst some, if not all are minor, they could lead to the callsigns not being recognised by the voicepack.
Here's a quick "checklist"
1. Red is not good

If after creating your callsign, you have a screen like this, something is not right.
2. Missing sound

Pretty straightforward, the sound you created has not been copied to all voices. Very Important you must listen to all voice reproductions of the callsign as sometimes, 1 or 2 voices will not be "saying" what you thought they were.
3. Title Case

The callsign name (in the circled area) must always be Capital letter followed by lower case - eg "Stewart". this applies to all words - eg "German Air Force". It must also match the callsign name at the top (which is all capitals).
4. Format

When entering the description of the callsign, you should put the name of the country in brackets after the description - eg F-15 493rd FS (United States). This one does not effect the callsigns, but it does stop the dreaded red highlights.
Hope this of some use.