Hi Robert, it looks like you're all set up to make a trim there.

The steps are - first select the object to be trimmed, like this:



Now run the Edit > Trim command. The command prompt in the upper right part of the window tells you what MoI is expecting you to do next, here it says to select cutting objects. So at this stage select your cutting curves (no need to pre-project them, trim has projection built into it already). So select the 2 cutting curves like this:



Then to signal to MoI that you're finished selecting cutting objects, push the "Done" button or right-click in a viewport which is a shortcut for "Done".

You will now be in the final stage of the Trim command, the prompt will say: "Select pieces to remove or push Done to keep all". So at this point if you want to discard some piece you can pick that piece and then do Done/right-click, if you want everything to be cut up and all the pieces left behind then push Done/right-click without selecting any pieces to discard.






Let me know if you are still stuck.

- Michael