For adding a line after 225, you say it does a correct indent of 6, but at that point in the attached file, it doesn't look like 6 would be right. Is that the wrong line number?
Could you post your user.config.xml, I'm not seeing any problem on the second case, even after I changed the settings to tab +4. Need to see if some other setting is coming into play when it should not.
Also if you close your project, and close all of the files, exit from SlickEdit, and then restart, and edit that file, the behavior is still the same? (that's a roundabout way to see if some setting is being improperly cached).