BuildCraft version: 7.99.14
Forge version: 14.23.2.2611 (recommended)
Link to crash report or log: N/A
Singleplayer or multiplayer: Singleplayer
Steps to reproduce: Right click on a filler
Additional information: The interface don't want to open, even with a crouch click

please update to 7.99.15, you might need a compat test build from discord, we had issues with this before that should be fixed

GUI of filler will not open if it hasn't properly set up volume box or marker box.