I don’t think that is the problem – I think the problem is that you have so many lines in the top section of the dialog (someone earlier in this thread asked what the term was for this section, unfortunately it doesn’t have one). Look at the error message in the Error wizzrd – negative rectangle height. It’s trying to position an element in the dialog and there is no room for it. Of course it should not fail with an error message, it should just refuse to add more elements, so that is a bug, which I have added to the list.
For now, you should be able to get the dialog closed using the Escape key.
In any case, I wouldn’t recommend using this dialog with so many options. Personally, I would go nuts trying to manage this in a dialog. I would recommend doing this with a procedure. That is especially the case since apparently you are trying to work with non printable characters (in this case tab). You’ll have no problem doing that in a procedure. If desired, you can start by using the dialog to record a procedure with a few elements and then expand it.
Keep in mind that the replace( function now allows multiple replacements in a single function, so you don’t have to nest a bunch of replace( functions any more. I think this procedure is much simpler to set up than the same set of replacements in the Morph dialog would be.