We need more information. In particular, what version of MEP are you using? What exactly are the steps you are taking? Which collage are you trying to apply?
Meanwhile, the general approach is:
1. Choose your collage, to suit the number of objects targeted. They are grouped into categories, first portraits and then landscapes, and within each of those by number of objects.
My apologies as I was out of town for a few weeks. To answer your question the version is Movie Edit Pro MX Plus. The steps for my example are: select the collage effect ([>]4obj.03(16:9)) and drag it to the first clip. The results is it uses the first clip and then duplicates the second clip on the 3 remaining spaces of the collage. I have tried other effects with different clips and I get similar results, mostly random (no control on the outcome). Any input would be greatly appreciated.
I assume you've tried the obvious step of re-opening MEP MX, starting a fresh project and placing only 4 objects in track 1, all of which play OK before you apply the collage?
The symptoms are what I'd expect if two objects (probably 3 and 4) had been deleted or moved or are otherwise inaccessible. (You haven't accidentally set the number of tracks to 4 by any chance?)
Also I expect you've tried File > Settings > Reset...
On my XP PC, that particular collage is based on the 99 KB (100,828 bytes) file:
C:\Documents and Settings\All Users\Application Data\MAGIX\Movie_Edit_Pro_MX_Premium_Download_Version\VideoEffects\Collage\picturemix_08.ctf.
Do you have the same file? If not, unzip and try this copy:
Has this problem always been present? And is it consistent? IOW, you can specify the collages that do work correctly and those that don't, and they remain the same from project to project and session to session?
Thanks for the input. I reset the software and tried the same effect to the same clips and got the same result. I tried other effects to the same clips and got similar results. I searched for the the "CTF" files and could not find them. I have Windows 7 and the path you provided is different so I could not replace the collage effect. I then started a new project and the same effect worked as expected. I went back and reopened the original project and applied the same effect to other clips and it worked as expected. Don't know why MEP doesn't like the original clips but I guess I'll move on. Thanks again for your help on this.