I can perhaps say something about the second question. I apologise in advance for tooting my own horn, so to speak, as my knowledge derives from a paper I co-wrote years ago with Takashi Kimura and Arkady Vaintrob: http://arxiv.org/abs/q-alg/9602014 .
In the approach to Vassiliev invariants coming from Chern-Simons theory, one constructs a "universal weight system" from some Lie-algebraic data. In the original work of Bar-Natan and of Kontsevich, the data consists of a metric Lie algebra --- i.e., one possessing an ad-invariant inner product --- and a module. However this extends to metric Lie superalgebras and more generally to metric Yang-Baxter Lie algebras, thanks to work of Arkady Vaintrob.
gl(1|1) is a metric Lie superalgebra and in the paper cited above we worked out its universal weight system. It has two parameters (corresponding to the generators of the centre of the universal enveloping algebra) and setting them to specific values one recovers the weight system of the Alexander-Conway polynomial.
We also show en passant that one can obtain the same universal weight system from a solvable four-dimensional metric Lie algebra, so that in fact one does not actually need Lie superalgebras at all in this case.
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