I used to be able to specify if the shop should be run under https in general under the
Configuration Director > Miscellaneous Settings > SSL Setup
by checking the 'Enable SSL' in Parallels Business Automation > Standard Web Tools boxes next to the name(s) of the web tools however it is not possible to do that anymore.
It was possible to edit this setting in OBAS 4.3.x, but since the version 4.5 it was disabled.
Please see the OBAS 4.5. Release Notes page 10, at the bottom of the page:
Important: Having been once enabled, SSL cannot be disabled anymore.