1. You can change the "Abilities" of the Hydra and add the "Infestor - Infested Terrans" ability to it.
2. "Stats - Range" on the "Infestor - Infested Terrans" ability.
3. I believe this can be changed in the "Infested Swarm Egg Timed Life" behavior. When this behavior expires, the egg "morphs" to the Infested Terran.
4. In the "Infestor - Infested Terrans" ability, change the "Ability - Produced Unit" to "Baneling." Also change the "Ability - Produced Unit" of "Infested Terran Lay Egg" ability to "Baneling."
5. What do you mean?

You make it sound so simple :'(

@no. 5 - Like, an infestor spits the egg from the back of it and does like a little jerk.
How can I make the hydra do something like that to make the egg spitting like plausible aesthetically?

That's in the events of the hydra's actor. You can have it so that when the ability starts, the hydra plays it's "Spell" animation or something.

You can check all the animations a unit has in the model previewer. The hydralisk's attack superior animation would probably do well for what you want. When you get into actors and models things tend to become much more confusing, I would recommend reading all the stuff on actors that we have in our wiki (limited amount) and other places to get a good grasp of them.

You would want to add a new event to the hydralisk's actor and the event would be something like Abil.LaunchBaneling.SourceStart and then for the actions you would have Animation Play. You can set the name to whatever you want as long as it isn't used elsewhere in the actor. Change the animation properties to Attack and then the second drop down to superior. Thats pretty much it, things will be more complicated in getting the egg to act like you want it to (launching from the right spot, playing the right animations).

It isn't inaccessible, actually. You can use a program to grab the maps, including locked maps, from your cache fairly easily.

What program would that be?? I want it

There is, in fact, a 'Jumping' ability type, just as there is a 'Teleport' ability type. They do pretty much exactly what they say they do.

I thought the "Jumping" ability type was more for things like the Reaper's jump, rather than a targeted "jump to the location" type of ability.

Yep... As far as I know the Jumping ability type is a passive / mover related / pathing type ability. Like the Collosi cliff-walk (although that's done purely through movers).

To create a jump ability (from point a to point b), you need to either use Force Effects, or get creative with a Launch Missile and a Teleport on impact

No, in fact, I was wrong - there's no jump ability type, but there is a Jump behavior. Rather odd, in fact - it does seem to interact with movers, but it has effects all by itself. I just looked at it and it looks like it's designed mostly for cliff jumping - but perhaps it could be adapted to a jump type action?

Otherwise, yeah, you're stuck with force effects and/or LM/teleport effects.