Hi Martin Zarney,
I think some of these guys may be making this much more complicated than needed. The ACORN plc since 4.50 has a lot of potential customization with generalized Outputs. The OUTPUTS1-8 that you can select in the wizard and M94M95111-126 provide you with a lot of outputs that can be toggled via a simple M94/M95 command or in the case for the Outputs1-8, M61-M68 and M81-M88.
As suggested before, if you just need to activate Output1 to turn your spindle on and Output 2 for your Air. I Suggest assigning your outputs to be SpinFWD for Output 1 and Keep Output 2 assigned as "OUTPUT2" in the Wizard. After doing this you simply need to edit your M3 macro and make a Custom M5 macro. This will most likely be easier than trying to create your own plc logic and compiling (however can be done this way as well).
Now, All you would need to do is Add M62 to your M3 command and add M82 to your M5 command. M62 will turn on your second output with M3 while M82 will turn it off with M5. Alternativly you could instead use the M94/M95 command with number /62 in the macros.
Just to prevent this from getting too long, i have two modified M3 and M5 macros attached with added M62 and M82 to turn the assigned "OUTPUT2" On and Off with your M3/M5 that you can use as an example to make your own modifications in the future. These should be working macros that you can drop into your cncm/cnct directory and as long as the outputs are assigned as mentioned above should work for you.
If you want to get into learning how to modify your own macros i suggest checking out the following documentation that can also be found on the Acorn Documentation Forum Post and on the Centroid Website.
Acorn Documentation: viewtopic.php?f=60&t=3397
Introduction to Macro Programming: https://www.centroidcnc.com/centroid_di ... amming.pdf
Centroid CNC PLC Manual: https://www.centroidcnc.com/centroid_di ... manual.pdf
And check out the video link for a series on PLC as well in my signature.