Custom button layout and mappings are allowed
Custom button configurations are allowed
Left + Right to do a SOCD Double-block on the other hand will get you banned from the tournament as that is exploting a glitch in the game code (as well as any other game exploits/ glitches).
Only 1 game has this as a issue, that was the vanilla Marvel vs Capcom 3, Ultimate Marvel vs Capcom 3 has addressed the issue.
Which I am sure Evo will be going to U MvC 3 in 2012 (as U MvC 3 has a number of other re-balancing as well).
Reasons Hit box is still legal is that the double block is possible on any controller (pad, stick, keyboard, hit box or what have you, see Hit box threads).
Hit Box brand Hitbox controllers have custom firmware to be anti-SOCD. And Toodles made a SOCD cleaner board for custom and mods controllers.
Evo is not and will not do SOCD checking because the lack of resources, time and man power (staff) to check every single controller. It is just not feasible, and is Mr Wizard’s final ruling on the issue.
As for Macros, In game Macro such as 3X punch and 3X kick, taunt, throws, tags and anything that can be selected in the Button config menu is legal.
Any macros on the controller side, such as setting up a single button to do a 1-button Shoryuken is illegal
Use of Turbo is also banned. Having these features on your controller is allowed but you can’t use them (at all) or the majority of retail arcade sticks would be banned.