Hi Budy

Do you have the correct volumes checked for the source and destination.
Clear metadata as well
CONFIGURATION -> volume manager -> Vol. replication -> Volume replication mode.

Could you also try with a smaller volume size

Increase Vmalloc
From the console CRTL-ALT-W -> Tuning Options -> Vmalloc

As for deleting Logical Volumes:
Delete any replication task that are using the LV's that you want to delete
In the action pull down menu select expand LVXXXX
CONFIGURATION -> volume manager -> vg[nr] -> Function: Volume manager.
then uncheck "Use Volume Replication"
Ckick Apply
This should turn the X to red
click on the red X to delete the LV