Exactly. You may not use it in a commercial environment. You're not supposed to use FBSL for resolving your business tasks or to even have it installed on your office computer unless you have negotiated such a possibility with the FBSL copyright owner.
FBSL has been primarily designed for education, self-education, and fun.
I can however reassure you. When FBSL v3.5
Final is out, it will have a much more permissive license enabling you to use it for any legal purpose without restriction, including its use in business environments or for developing commercial projects.
Are you really so much a legal entity here anyway rather than just a hobbyist BASIC pragrammer, Brice?