the quick and dirty way would be to go to wp-content >> themes and rename the theme you want to use ‘default’ (you can rename or delete the actual ‘default’ one when you do this)
Thanks for the answer.
That might cause a problem at every upgrade. I would prefer to avoir such a thing. Is there a none-quick and none-dirty way?
there is a plugin download from here
wpmudev.org
plugin name is default blog templates..that will do
Yes, this is a WPMU question. Use what Mohit suggested or search the WordPress plugin repository.
Unfortunately, this plugin doesn’t exist or have its name changed 
Default settings for new blogs for WPMU plugins DO exist. Again, this is nothing to do with BuddyPress. Look on the WPMU forum.
function change_template( $blog_id )
{
switch_to_blog( $blog_id );
update_option('template', 'bp-sn-parent');
update_option('stylesheet', 'YOUR_TEMPLATE_NAME');
}
add_action( 'wpmu_new_blog', 'change_template' );
put the above code into your bp-custom.php file and it’ll use the template you specified instead of YOUR_TEMPLATE_NAME.
Thanks a lot, this solution is really helpfull and so easy to implement.
DJPaul – I fear you are wrong – this is EVERYTHING to do with buddyPress – BP KILLS WPMU themes when that pig of a 1960’s ice cream parlour decor known as bp-sn-parent and it’s cantankerous child bp-default take over the entire site.
The plugin “Default Blog Templates” is available from the WPMU Plugins repository but the “bluddypress” default theme also kills the settings in that, and takes control of the blog admin pages too, such that saved drafts cannot be previewed and the top left button to “visit site” simply returns the user back to the blog admin dashboard.
I don’t know if this is specific to just v1.1.2 on WPMU 2.8.4a but it’s getting closer to a rip-out and ditch for BP for me. At least WPMU was working and ready for custom development before BP went in.
Thanks Travel-Junkie!
Trying to implement this instead of making new users switch themes.
One silly question (sorry I’m a newbie):
– when replacing “YOUR_TEMPLATE_NAME” in the code, do I use the folder name for my member’s theme (in my case “bp-default_members”) or do I use what I’ve called it as “name” in the CSS
Thanks!
@deniscarr
it’s the name of the folder holding all your theme files
