i understand if they only support clients. this is finance after all. if you want to make money and do open source you gotta charge for support or charge for an add on. the core is still open and free. like you said if you don't want to use glean, don't use it.
i use glean without...
anti virus warnings for glean you can ignore, they are false positives.
glean seems like a good value to me, you don't pay anything for testing or even live trading until your strategy is making money.