I noticed two minor UI problems with the Add/Cancel buttons:

1. They are in the order 'Cancel, Add'. This seems to me to be wrong, as in different to typical Moodle confirm boxes etc. Could the order be reversed?

2. Should there be a little space between the buttons? Also, the Add button is much smaller than Cancel - I know this depends on language but how about adding some non-breaking spaces around to make it a similar size?