I have had another look at this problem. First, I'm fairly certain that it is the 'geomCustom' that is causing you the problem.

This solution worked for me, and it's quite simple, you don't even need to delete the rsr. If your figure is V3, then just load any V3 character that does NOT contain a 'geomCustom', before you load the character that does contain a 'geomCustom'.

The problem only seems to happen if you load a character that uses a 'geomCustom', then load a character that does not contain a 'geomCustom' afterwards. As long as I loaded a "normal" character first the problem did not happen.

If for some reason of posing or composition you want the character with the 'geomCustom' loaded before the other character, or you don't know which character contains the 'geomCustom', you could just load the default V3 first then hide it (select 'Body', then from the menu bar; Object > Properties > Visible). After that you should be able to load any V3 character you like in what ever order you like.

This worked for me, I can't guarantee it will work for you, but I'm willing to bet a cookie that it will ;)

P.S. This bug only happens in P4 (and perhaps earlier vrsions), later versions are imune.