And because it's late and I'm forgetting stuff, moving capital ship abilities to frigates is a bit trickier.
Capital abilities have this:
maxNumLevels 3
levelSourceType "Intrinsic"
minExperienceLevelRequired
Level:0 0.000000
Level:1 2.000000
Level:2 4.000000
"Intrinsic" means the ability's level depends on the level of the ship (1, 3, 5 respectively, the files start counting at 0 rather than 1). Since frigates don't have levels, this won't work. So all frigate abilities need to have:
maxNumLevels 1
levelSourceType "FixedLevel0"
For the ability to be always "on". If you're curious, abilities that you research look like:
maxNumLevels 1
levelSourceType "ResearchWithoutBase"
improveSourceResearchSubject "RESEARCHSUBJECT_ABILITYACCESS_SABOTAGEENGINES"
As an example
But since none of the capital ship abilities need research, you don't need to worry about this one.