Firewall/NAT

I am running 1.3b2 and I have the following setup:

about 30 IP's in one continuous range protected by MW
20 of those IP's in the 1:1 NAT
42 rules for the 1:1 NAT (such as opening FTP, HTTP, SMTP, etc.)
running from CDROM and config saves to Floppy.

the problem I am running into is that if I try to add another rule or two, monowall tends to blow up and corrup the running configuration and saved configuration and go into a weird state.

Is there a rule limitwith this version of MW or is there something else I need to look at to correct this issue???

thanks!

There are people with a LOT more rules than that, though I'm not sure about 1.3. Does the same thing happen with 1.2?