All 3 Uses of

however

in

Going After Cacciato

He must return at last to a world as it is, however much in conflict with his hopes, and he must then do what he can to edge reality toward what he has dreamed, to change what he can change, to go beyond the wish or the fantasy.
Chpt 44 *

however = regardless of how

There were times when a fast march along a trail, however perilous, was preferable to a slow march through tangled, hostile country.†
Chpt 37 *

Definitions:

(1) (however as in: However, complications may...)
though (or another expression that connects contrasting ideas)

(Based on idea 1 we might not expect idea 2, but this is a way of saying that even though idea 1 exists, we still have idea 2. Synonyms include in spite of that, despite that, nevertheless, nonetheless, on the other hand, in contrastand but.)
(2) (however as in: However much she tried...)
to whatever degree (regardless of how much; or whatever unspecified amount)
(3) (however as in: However you do it, get it done!)
in whatever way