I have had a problem for a while with my chain dropping a lot.
I have a Quarq Elsa power meter that has SRAM powerglide compact chain rings on it.
i am using a shimano ultegra FD. and Shimano ultegra CN-6701 chain.

after a year and a half of constantly dropping the chain, i took it to my LBS today, and they suggested i try putting on some FSA chain rings since no one else seems to have this problem. the chain coming off consistently causes me to knock loose the PM magnet.

anyway, i took in my original FSA crankset/chain rings for them to install. that is opposed to buying new chain rings.

i wanted to ask you guys if the chain rings are usually interchangeable? like could i go out and just buy any compact set (110BCD) and slap on the PM spider and any set of cranks and have them go?
does the PM spider need recalibrating? are there special interfaces that i would have to worry about?

thanks in advance.