My ScorePanel has FirstIndex and LastIndex for tracking which lines are displayed, and the display is changed by changing these values. We know that they are changed externally if they change outside of the rendering process.

If FirstIndex changes, we add lines from start to finish and if LastIndex changes we add them backwards (ie when turning back a line/page and we know the last line but not the first).

Moving to .Net 4.0 fixed an annoying bug that caused something to hang on to fonts, but caused a new exception (also to do with fonts, but perhaps is legit).

Removing Lines from ScorePanel Children triggers another render loop. Err.