- free upgrades do not let the tooltips error out.
- free technologies can be researched.
Shouldn't the sele paired tech benefit from this immediately?
Trying to train a unit without a cost component errors out (I tried brittain dogs, probably happens with all units)
Slightly more offtopic (maybe out of scope): disabling the resource tag in the cost component errors out (tried with ptol houses).
Note that this patch does not add any functionality, only sets a default value.