I don't know about any glitches, so I can't give any comments on that. I'd rather like to see a non-glitch run though (and slam that 16 minute border on PAL speed), but that's my personal opinion.
Some feedback points:
- The octopus route is much slower then the normal route. I also tried it when i ran the game.
- The money collecting can have some better planning. Liked your first level though!
- Map 4: At the end of this level (after the long text) Alex doesn't have to pick up the helicopter. He will have it anyway in the next map (also: see my speedrun).
- Map 5: Fall in the water earlier.
- Blue castle: : in the room after the 3 moving ground flames you can go a bit faster by pressing right while falling down near the end of the room (pretty hard to describe but see for yourself).
- Blue Castle: get past the flames at the end with invisibility powder, buy this in an earlier shop, eventually should be faster I think. (You also mentioned this)
Jankens castle: pretty early in this level there are 2 flames and a scorpion. It’s possible to go faster here. (See SDA video)
These are the points I can come up with. The rest of the run seemed strong. Hope it helps you to get a better time.