[Wulfmann]

Any mistake in the RND causes CTD.
In your outside SH3 folder (where you keep SH3 DLs etc) I advise making a RND folder to save RND.mis files.
When ever you want to change anything, copy the current working RND move it to the RND outside folder and change the name to include the date you made this copy so you can reference it if required. Or make dated folders for each one as they cannot have the same RND.Mis name.
The convoys are RND Group 61-118 so are all bunched up. One way to improve them would be to make an entire copy of a convoy that stretches over too much time.
Now add it to you end of the RND file and change the name of it to the next RND Group number. Change the end date of the first version (to say ends on March 31, 1943) and your new version starts on April 1, 1943 ends May 10, 1945. Now you can double or triple the number of escorts change the composition of ships to reflect latter ones etc.
I have done this to a number of convoys and it allows better period ships and works well. So long as there are not any mistakes, back up and back up.

If you use mission editor save it "as" (as was mentioned) a new name. Now remove the old version to safe keeping and change the name to the name (RND.mis) of the old one and start the game with prayer. Couldn't hurt!

Wulfmann