If skills are greyed out, it means there's a syntax error in your file somewhere that's preventing the entire ability system from initializing. First read this post about enabling and using the error log - it's much more (and unnecessarily) difficult to debug a mod without it: https://forums.demigodthegame.com/399524/page/1/#2812350
Then make sure you're familiar with Lua syntax and are using an editor (like Notepad++) that has syntax highlighting, so you can more easily find errors, and use a non-destructive approach to changing ability parameters when possible, to keep the possible errors to a minimum.
For example, to change the energy cost of Spine Attack I, you only need to reference that one variable within its ability blueprint table, within the global Ability table. So start with a blank HDemon_Abilities.lua file in your hook path, and add a single line like this:
- Ability.HDemonSpineAttack01.EnergyCost = 150
Use one line like that for each ability blueprint to change their energy costs, making sure to change the name of each ability blueprint (HDemonSpineAttack01 in this case) referenced so the correct ability is changed. How/why you do this is described in much greater detail in several posts following this one: https://forums.demigodthegame.com/376116/page/1/#2635933
As for adding buffs, I'm not entirely sure what you're trying to accomplish there? First of all, that buff isn't being added to the ability in any way. There are two ways to do that, one 'automatic' and one manual, and usually the manual way (via actual ability function code) is the only way that really works for most abilities.
What do you want the buffs to be applied to? When do you want them to run out? You're creating infinite-duration buffs that, if added to the ability's Buffs table, would be applied to the TARGET of the ability, PERMANENTLY. I'm guessing you don't want either of those things, so you might want to do a bit more research on buff creation and usage by looking at some other abilities.
And remember to always start with one change at a time. Do simple things first, get those working in-game, and then add each further change one at a time (in chunks that seem reasonable to debug should an error pop up), so you know exactly where the problem is whenever you run into an error.