[karajorma]

The bit in my FAQ refers to solving the problem for retail FS2 not campaigns but it should give you enough to identify the cause at least.

I'm playing a mission but instead of the ship I'm expecting I just get a Ulysses fighter.

This is the result of installing a mod that alters the ships table. Although it can occur for any missing ship it is most noticeable when the affected ship is supposed to be a giant capship. The game goes to the ships table expecting to find a certain type of ship but can't find it cause the mod has replaced or removed that ship from the ships.tbl. When FS2 can't find a ship on the table it replaces it with the first ship on the table which in most cases is a Ulysses.
Fortunately the ships.tbl merely tells the game where to look for a ship so the ship hasn't actually been deleted Curing the problem requires that you find the mod causing the problem and renaming/moving it.
Go into your Freespace2\data\tables directory and check for a file called ships.tbl. If it exists rename it file to something like disabled-ships.tbl
If that doesn't solve your problem or you find no file by that name (It may be hiding else where in your FreeSpace 2 folder) your problem is most likely a rogue .vp file.

The Official .vp files have the following names

    * root_fs2.vp
    * sparky_fs2.vp
    * sparky_hi_fs2.vp
    * stu_fs2.vp
    * tango1_fs2.vp
    * tango2_fs2.vp
    * tango3_fs2.vp
    * smarty_fs2.vp
    * warble_fs2.vp

You may not have them all but if you have any .vp files other than these in your FS2 folder it is likely that this is the cause of your problem. Try renaming the extra .vp files to .vpDisabled or something similar or simply move them out of your FS2 folder (or into a new subfolder)

That will solve your problem but it won't stop it from reoccurring next time you install a mod. It also means that the mod that caused the problem will stop working properly. The problem is that you didn't install the mod correctly in the first place.

[Knarfe1000]

Thanks so far! Where do I have to install the nebulae-pack (don´t no the name of the developer)??

[Knarfe1000]

@karajorma:
I tried like you described. I have only installed derelict and Revenge, which are now in seperate folders in the FS 2 folder. But even now the Marco Polo is a damn Ulysses 

I checkes the data folder under FS 2. There is a subfolder called "tables" but it´s empty. I have no other .tbl´s found. What shall I do now??

[Knarfe1000]

I solved it. I just downloaded the newest english version, which includes new (?) ships.tbl and weapons.tbl. I copied these tbl. in my Revenge-folder and I saw the Marco Polo for the first time...

[Mobius]

Did you like it then?

[Knarfe1000]

Yeah! Not bad at all 

[Dan1]

I was not able to get the mobile beam weapon working with the SCP version.  Anyone else experience this?  I like it's overpowered effect in non-SCP version.