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I am considering this, but I am trying to see other reasons for pistons other than jumping. Controllable rockets can fill the same function. What other things would you use the pistons for?
I need to fix the delete UI.
Crashtastic version 0.4.4 added support for hotkeys in the editor for all the available parts.
I rewrote the UI backend for the editor, so this issue *should* be solved.
Crashtastic version  0.4.4 includes the ability to individual tune the power of the rockets, and on some levels you can assign a key to control them directly.
Can you look in the host-file (C:\windows\system32\drivers\etc\host), and remove any reference to  api.crashtastic.com , and try logging in again?   If that doesn't work, can you send an email to support@crashtastic.com with your output_log.txt file from the crashtastic_data directory.

Thanks!
Thank you for your purchase! I am glad you like the game!
Is the FPS low on all designs (like 10 pieces)? Or just larger designs (40+)?