This is what helped me.
Right click My Computer then click on Properties.
Will bring up System Properties window, select Advanced tab.
1st section is Performance (you must be logged in as Administrator), click the Settings button.
1st tab is Visual Effects.
Default is, "Let Windows choose........my computer" ,
Instead select , "Adjust for best performance",
Or if you have some experience with Win XP , select "Custom".
After these changes select "Apply at bottom.
Seeing that you are using a Mac Laptop fbass, I would try the best performance selection 1st.
Reopen Advanced Tab, reselect Performance Setting button
Next click the center Tab "Advanced".
Under "Processor scheduling" and "Memory usage" sections, select "Programs"
(under memory usage if problem persists select "System cache")
Finally in last section under Virtual memory IF it does NOT have 2046MB as "Total paging file size for all drives:" click the change button and set Paging file size to 2046MB.
Once this is done select OK at bottom.
Win XP or any Win OS are memory hogs IF you let Windows handle your ram. Before I did these steps my older system a PIV 2.4 gig system with 1.5 gig of ddr 400 ram would get the "bad allocation" error msgs.
After wards I could play RoM without CTDs AS LONG AS I did NOT play the Mega Packs. Core RoM without REVMod played smooth with up to 20 AI. But with RoM 2.5 and up I had to play without BarbCiv and Start as Minor options as well.
I have since built a new comp with win XP Pro 64bit OS, Dual Core 2.8gig CPU and dual Bios Mobo with 8 gigs of DDR2 1066 ram and a Vid card, Sapphire HD 4650 with 512 ddr3 ram, and I don't have those old restrictions. But not everyone who plays RoM is gonna build a new computer either.
JosEPh