I found these lines of code in the "help.txt" file.
OM_IS_A
Disable Internal Sale
The default setting of #Internal Sale# is #Disabled#. Competitors are allowed to buy your products.
~
OM_IS_B
Enable Internal Sale
The default setting of #Internal Sale# is #Disabled#. Competitors are not allowed to buy your products.

I think there's something wrong. It says that competitors can buy our products when the option is disabled but they can't when it's enabled not to mention the "disabled" which are put for both times...
PS: there is the same problem with the post release version
thank you for your feedback