If you post your current config (please sanitize it to remove passwords etc) you will probably get more accurate help than this.
There can be a few different reasons for this. Most probably it is not the creation of a configuration group that kills the l2l-tunnel but the way it is applied.
* Your remote-vpn is probably configured with a dynamic crypto map which is applied to the static crypto map. Make sure that this dynamic crypto map has a higher sequense number in the static crypto map than the sequense number used by your static tunnel.
* If you are using preshared-key add the "no-xauth"-keyword at the end of the "crypto isakmp key"-command to make sure that your l2l-tunnel isnt xauthed (asked for username/password).
Br Jimmy