Very high levels of AST (more than 10 times normal) are usually due to acute hepatitis, sometimes due to a viral infection. With acute hepatitis, AST levels usually stay high for about 1-2 months but can take as long as 3-6 months to return to normal.
MFMA recommends the relative humidity level for a concrete slab for a non-glue-down maple floor system be 85% or lower and for glue down systems the concrete slab relative humidity level should be 75% or lower before installation.
I've always heard to keep it at or under 55 relative humidity to avoid mold and moisture problems. I would think 75 would be a wee bit damp... but every home is different.... And I could be wrong. We have one in our finished basement (split level house - half below and half above grade) and I keep it at 50% RH.