The double jump happens anywhere there is a ledge.  Sometimes it happens, sometimes not... *shrug*

Not sure what you mean by the double jump thing. The jump animation sucks because i have to move a certain number of pixels in a time period, and your eye doesn't like how it looks when i skip that many pixels moving your character.
As for the glitch between pewter and route 3 and why route 4 isn't attached, its because I assume that maps are directly centered over each other. For most  maps this works fine and saves me some space, but it isn't always the case. I'm not sure exactly how I want to handle this yet so for now it will just be like this.
Viridian forest is not done, if somebody wants to make all the new tiles and map them out go for it. Fyi if you add a new tile that is collidable, I need you to give me the tile number, otherwise it won't be collidable in game

Yeah ok so thats what I thought you meant. Interestingly its not exactly what I thought (although thats part of it). The main problem was the shadow and the way your eye was perceiving the ground relative to it. This should be better

Yeah ok so thats what I thought you meant. Interestingly its not exactly what I thought (although thats part of it). The main problem was the shadow and the way your eye was perceiving the ground relative to it. This should be better

He still seems to wriggle when he's just over the ledge.

Same here. You may want to try running the game in WabbitEmu with 1% speed setup or something and with faster LCD motion blur to notice it easier.

The "wriggle" you guys see in the air is the movement of the char 5 pixels down, so he can reach his destination fast enough. Not sure how much I can do about this. Also another update, I've begun reworking part of the core engine, because unfortunately I wrote it broken (mainly cuz I didnt know any better ). Its working better now, but they're are still a lot of bugs to find and fix so don't expect a release anytime soon

I've always preferred Blue over Red.  I'm one of the few.

We should start a club. I'm in favor of releasing both versions: the differences are minor, correct? It wouldn't be that hard.

<3 yellow.

I always found it harder to start off, seeing as you start with a pikachu, who isn't very good against rock type pokemon (the first gym leader).  But I think that it becomes way easier after you beat the first gym leader.  The only thing I didn't like about yellow, they fixed the missingno. glitch