user.reg and winedbg

They key in user.reg that controls whether winedbg pops up in its
own window or in the shell in which wine was started seems to be
getting ignored.  When I set "UseXTerm"=dword:00000000, and run my
app, it crashes and brings up winedbg in a separate window.  When
I look at user.reg again, UseXTerm has been set back to 1.

The reason I need this is because when my app crashes, the backtrace
is so long (~40 frames) that I can only see the bottom (mostly
useless half).  Is there a way to increase the size of the winedbg
window, pause bt's output (like piping to more in a shell), or display
only part of a back trace?

-Steve