In general, your best bet to figuring out the first three of those five lines is finding a pre-existing ability that is similar in use...that is a very vague piece of advice but the more you do this the better you'll get at it...
buffStackingLimitType
This has to do with how the limit is applied...the two values for this line I'm familiar with are "ForAllPlayers" and "PerPlayer"...in general, you want "ForAllPlayers"...this means that if the stacking limit is 3, then the targeted ship cannot feel the effects of more than 3 debuffs even if multiple players are targeting with that particular ability...
"PerPlayer" means that I can only affect you up to 3 times but if a 2nd player comes in, he can hit you with the ability too, allowing it to stack 6 times...an example of this is embargo, where multiple players can be stealing resources from the same planet...
allowFirstSpawnerToStack
A good example is incendiary shells...the current stacking limit is 3, but because allowFirstSpawnerToStack = TRUE, a single Marza actually can stack this ability three times by itself...this means that the 3/4.6/6 DPS actually results in about 9/13.5/18 DPS despite having only one Marza...however, if allowFirstSpawnerToStack = FALSE, then you would need 3 marzas in order to stack the ability 3 times...
buffExclusivityForAIType
This is the trickiest, and I'm not entirely sure about it...in general though, find a similar ability and go from there...you do not need to find necessarily an ability with the exact same effect, just something close...for your two abilities, I'd compare them to the gravity warhead that the vasari space egg has or the GRG on the Kol...
isInterruptable
This indicates whether the ability can be interrupted or not...for example, Missile barrage is interruptible...this means that if you hit the marza with ion bolt, detonate antimatter, phase out hull, etc. then the missile barrage will stop...this is often one way to balance very powerful abilities...missile barrage comes in 30 or so waves IIRC, so if you interrupt it at the 10th wave then your fleet only suffers 1/3 of the damage...in general, you don't want abilities to be interruptible unless they are very powerful...in general, really only applies to abilities that use periodic actions or actions over time...
isChannelling
This means that the ship will stop using the ability if it is give new orders...a great example is shield regeneration on the Progenitor...if you tell the ship to move while it is using the ability, the shield regen will stop and you will only get part of the buff...the ability icon will flash with a yellow outline if it is activated and is channeling...this is, like the previous line, only relevant to abilities that act over time or are periodic actions...channeling is more restrictive than being interruptible because giving the ship new orders also cancels using the ability...
As for why you are having problems, I can't really help you without seeing the files...either link them or just copy all the text and make it a post...