@index4d said in Error: Attempting to extrude with no tool selected.:
But pls make a suggestion if I should describe my plan for a tool switch.
… Which lets me ask whether your tool switching works, at least 'somehow'. I don't have the faintest idea what mechanism you use to alternate between T0 and T1. In my case, I use tfree to move a tool out of the way and tpost to activate it. You use tpre instead, but at least the M116 gCodes should be in tpost. As far as I can see, you happily mixed up commands to release one tool with others to prepare the other one: it's better to keep them separate. Did you read and follow the - well written - guidelines?
After you got your gCodes sorted into the proper macros, it's time to test them, one at a time. If you call such a macro from the command line with
M98 P"myFancyMacro.g"
, you receive messages on syntactical errors. In addition, you can focus on your coupling mechanism - I think you call this with
M98 P"/macros/Coupler - Lock"
Did you test this one?
BTW, there's yet another way to test a macro: comment-out all lines you don't need in the first place, e.g. some moves and all heater commands. By this, you can add functionality step by step, which makes it easy to spot problems.