No other than towing and then checking after a few miles. You could either try www. electrolux.co.uk or go on line to one of the free language translation sites. I have a manual for the RM 4230 - 4231 can't see they would be much different, just more tarty.
Interested then go to page 17 of above forum page listing for caravans and motorhomes and look for THETFORD PORTA POTI BENCH TYPE WON'T FLUSH' in the reply is my email address. Send yours and I'll copy the manual. I'll be away in two days time for a week so be quick as I don't access emails when away.
Can't put it in this answer, forum no longer allows email address insterts.
Bob
May 2009