Grunch. OP, please put some spaces in your walls of text. It will make them easier to read. I added some.
Hand one: You're using the word equity wrong. Equity is what you have based on your chance of winning the hand. You are actually figuring pot odds, though describing them in percentage, which is fine. It's what I do as it's easier to compare to equity.
You are being asked to pay $27 into a pot of (total, including your call) $131. 27/131=20.6%. You figured it in the correct method, your call divided by total pot, but I think you inflated the pot. Not sure where you are getting $160. It looks like you put the $10 into the pot from the players who called at first and then putting $37 in for when they call the shorty's shove. Just like you, they are only putting in $27 more.
Obviously, you aren't going to flop a set 20% of the time, but I still think it's fine to call given likely IOs. You could also try to isolate with a big raise, as the 2 callers ranges are capped pretty low here and the OR should have re-raised if he had a premium too.
Your first call you forgot to put your money into the pot when you did this. I usually don't include the blinds in my calcs, as they will basically cancel out the rake and it makes things simpler, so your 10 should be divided by a total pot of 40 (OR's 10, 2xcallers 10's, and your 10). Your call represents 25% of the pot.
As you mentioned, the IOs are more important here than the direct odds though. This is a call to set mine all day long.
Hand two: Fold pre AINEC. K5s in MP is hot garbage. AP, never folding OTF but raise is iffy depending on whether Vs actually have fold buttons.
AP with the jam, you are being asked to pay 275 into a pot of 943 (48 pre, Maniac's 115, Tight's 390, your 390), or 29.2% of the pot. If maniac calls, pot will include another 125, so you will need less equity (but also have less, as he'll have some). In that case, you would be paying 25.75%. Again, you have the method right, but seem to be adding money to the pot twice. If maniac called your raise to 115, he put in 115 total, not 115 plus the 30 he originally bet. His call only cost him 85 more.
Against AA, you're laughing. You have 47% equity, way more than you need. Against a range of all the possible sets you have 29.2% equity, exactly the price you need, though it actually depends what set. If he showed you TT, you should theoretically fold and if he showed you 33 you should call.
Realistically, of course, his range is made up of a bunch of things. Let's say Tight's range is Ac9c-AcQc, JcQc, all sets, and 6 combos of overpairs. He's tight, so he shouldn't ever have 2-pair or an open-ender here. Against that range you have 43.9% equity, which is obviously plenty.
If maniac calls, he has the all the draws and a bunch of two pair, but probably no overpairs or sets, as he would have re-raised you himself. Let's start his NFDs at Ac2c and also give him Qc9c+ and 8c9c, give him all the suited two-pair combos and OESD combos. Against those two ranges together, you drop down to 26.8% equity, which is still more than the 25.75% you're paying, though obviously maniac folding a NFD-heavy range is good for you.
I'll do your theoretical on in a separate post, as this is already getting really long.