If you missed something in the help section, check this page, it contains few links.
Your file contains the wrong version of RPG Maker XP, follow this guide to know how to fix it!
Using the disable_reason function for a move. Using the on_move_disabled_check function for an effect.
Set them up in Pokémon Studio and make sure the map properties are correct with F9
A quick tutorial going over how to set up a GTS system!
Guide explaining how to adjust Pokémon position on the screen
If you need to compile your game, here is the procedure to follow.
If you want to contribute to Pokémon SDK to fix bugs or add features, you can follow those instructions.
If you need to version your game or simply edit some rxdata files, here is the command to convert them.
If you need to translate your game, check this page to know which command you can use to generate your game texts related CSV.
As for battle sprites, name the cry according to the format ID_FORMCry.ogg.
By using the function move_blocked_by_target? for a move and on_move_prevention_target for the effects.
Usually, crash generate a file called Error.log, follow this guide to know what to do in case of crash
RPG Maker XP (for now)
PSDK was created by Nuri Yuri and is now developped by many people, this page contain a little list