BuildCraft version: 7.99.22
Forge version: forge-1.12.2-14.23.5.2772
Link to crash report or log: https://pastebin.com/sUFN30xa
Singleplayer or multiplayer: Multiplayer(LAN)
Steps to reproduce: Build ComputerCraft Miner in Mystcraft dimension. Run controller computer from overworld and wait.
Additional information:

Pastebin Miners x16 --
Startup: 8jGd5n90
Miner: BikGhZxL

Pastebin Loaders x2 --
Startup: xTbKr3HN
Chunkloader1: j3ZTkJyR
Chunkloader2: cHy3Z1wu

Turtles have ender modem on right side and pickaxe on left side. Located in Mystcraft Age.

NOTE 1: For loader turtles you must place chunkloader in the turtle and have it place it up using lua command, it's not automatically done in the script.

Controller pastebin: VYqbJ4xa
Controller has ender modem on left in overworld.

NOTE 2: When I removed buildcraft(Tried removing computercraft and/or energy converters first but only removing buildcraft fixed it) to re enter the world then re added buildcraft later the power pipes turned to a non connected pink texture and the mining well pipes were invisible and still there without mining well(best I can describe it, I forgot to get screenshot of it before cleaning it up)

NOTE 3: Energy Converters was used to change my current(and wireless) FE power system to MJ.

Screenshots:
Complete Setup:

Power Converter Turtle 1:

Power Converter Turtle 2:

Power Converter Turtle 3:

Power Converter/Mining Turtle:

Wooden Pipe Mining Turtle:

Other 14 Mining Turtles:

NOT PICTURED:
The Chunkloader turtles have a coal chest in slot 16 and a stack of coal in slot 1.