Hey @halloleo,
Rule-of-the-thumb — never use Insert Text by Typing when Insert Text by Pasting will do.
It’s faster, and more immune to problems.
The problem you describe is peculiar. Can you post your macro with example text for the clipboard that fails on your system?
It’s very unlikely that Keyboard Maestro would delete characters when typing them, unless you’ve set it up this way in your macro.
Try testing with a basic keyboard shortcut with no modifiers like F1.
Make sure you’re not interacting with another utility on your system.
Make sure your typing macro isn’t activating another Keyboard Maestro macro by accident.
-Chris