SQL Server Reporting Services
Since as soon as you extend your mdx datasets manually you can no longer switch back into design mode without losing your changes, right
If that's the case, is there some way to disable design mode completely i'm finding that the GUI has the tendency to SILENTLY revert the dataset editor back to design mode while I'm busy editing a layout, thereby losing my carefully crafted MDX.
This happens to me alot - it's driving me nuts. I've written my MDX by hand and perfected it in the Sql Server Management Studio. Then I paste it into the "roll yer own MDX" of the dataset query editor. this works fine. I can then build a report. But then subsequently, if I go back to the data set editor - IT OPENS IN "GRAPHICAL MDX DESIGNER VIEW AND DELETES MY QUERY. 
Only thing I can do at this point is close the report without saving, then reopen, click view code, go into the XML, extract the dataset definition mdx, then go to teh dataset editor, allow it to destroy my mdx, then repaste it back in again. Fun huh
maybe it's that - I can't live without crlfs in my mdx!!
however, i sense there's a little more to it .. i often find this happens most often (but not exclusively) just after I've created a new report.
Anyway, no use crying abuot it, normally when the mdx gets killed by the editor, it is still available in the rdl so I just fish it back out of there and stick it back in the query editor.
And thank god for source control 