Importing multiple Unit/Ability data?

I was wondering whether it is possible to import unit data from multiple maps at once without overwiting the last imported data. For example...

I have 4 maps ; map 1,2,3 & 4.
I want to get data from maps 2 3 and 4 into map 1, however if i import map 2 data then map 3 data, map 3 data overwirtes all previous data. is there some way to group the data from 2, 3 and 4 together so they only overwrite the data in the original map?

Any help appreciated :8

Cant be done duck, u gota have the map u want to copy from and the map u want to copy to open , and manually press ctrl c, v....switching between maps.

Annoying as hell.

Yes, you can't just merge the unit data files because the unit/ability IDs will screw up. You can speed things up by doing the editing in .slks but you'd stil have to manually reassign unit IDs.