I think I have finally found the RaceSySurvey.Name bug! Thanks to Andrew for his database.
When I added the 'Real Stars' option, I also added a Fixed Name field to the System table so that real star systems would have a name that all races would use. This is created when a system is generated during a 'real stars' game and is blank in a normal game. If you enter a system that already exists but that you don't know about, the program checks to see if this is a real stars game. If it is, then the program gets the Fixed Name from the system table and uses that for your racial name for the system. If this isn't a real stars game then the program generates a name in the normal way.
The problem is that the check used at this point is as follows:
If rsExistingSystem!FixedName = "" Then
SystemName = GetSystemThemeName(SysRaceID, NameThemeID)
Else
SystemName = rsExistingSystem!FixedName
End If
This looks innocent enough and I didn't spot anything untoward during a read through of the code. Unfortunately, the fixed name field in the database is set to null and that isn't the same as blank. So the code interprets the if statement as false and tries to set SystemName = rsExistingSystem!FixedName, which causes an error 94: invalid use of null.
SystemName can't accept that so it stays as a blank variable. Prior to v4.71, that blank variable was then passed to the piece of code that tries to setup the race record for that system in the RaceSysSurvey table. That table is set up not to accept a blank name for the system so it generates the error that RaceSysSurvey.Name cannot be a zero-length string and refuses to create the record. Everything else in the system is still setup and the system does exist. You just can't see it. Any ship that goes through that jump point will still exist as well but you won't be able to see that either.
The one item of good news is that in v4.71 I added the following line of code after the above section.
If SystemName = "" Then SystemName = "System " & rsExistingSystem!SystemNumber
This was because I suspected the problem was in this area somewhere. I just couldn't pin it down. This means the only effect of the bug in v4.71 or later is that the System will end up with a name like System ### where ### is the System Number. However, that still means that if this error appeared before v4.71, then your database will have one or more missing RaceSysSurvey records. If this is the case then you can either add the missing RaceSysSurvey record (I'll post how on here if anyone wants to try that), or send me the DB and I will add them and send it back. This make take a little longer depending on how many I get

For v4.76 onwards I changed the code to use a global variable that is set true/false for whether 'real stars' are being used. This is used in other parts of the program already but for some unfathomable reason I didn't use it here
Andrew - do you want me to fix this DB or do you have a more recent one?
Steve