WordNet sense 1 (highly complex or intricate):

byzantine, convoluted, knotty, tangled, tortuous

WordNet sense 2 (complicated in structure; consisting of interconnected parts):

complex, complex

WordNet sense 3 (closed in or surrounded or included within):

enclosed

WordNet sense 4 (culpably involved):

concerned

WordNet sense 5 (involved in or affected by or having a claim to or share in):

interested

WordNet sense 6 (entangled or hindered as if e.g. in mire):

mired

WordNet sense 7 (loaded to excess or impeded by a heavy load):

encumbered

WordNet sense 8 (associated in an exclusive sexual relationship):

committed, attached