This last Asobo patch on Dec 22nd has corrected most of the issues in the US, but now the NEW issues are primarily in the Western US, hence in areas that were clean before. I have "rebooted" this MOD and it now covers the entire US. Also, Asobo is likely already working on a fix, so this is more of an interim solution. 

Important
Please report any anomalies you find while flying around the US in the comments, or over in this Forum thread.

Installation
Be sure to delete any old versions of this mod, and then copy the new files into your community directory.

Beyond the US
For other locations, see this mod - Elevation Fixes - Around the World

Release Notes
(R050a - Current Version)
Colorado - Added Aspen Area (KASE) 
Georgia - Major fixes from KRMG to 53GA and surrounding area (Dawson - Cave Spring)
Maryland - Minor refinements around Baltimore
Wisconsin - Fixed Lacrosse (KLSE) 

(R010 - R045)
California - Corrected Needles area, and spikes near KSBA & KCMA & KSQL, and a few NE of KSFO
Colorado - Spikes near Vail (KEGE - Eagle County/Gypsum) and Cortez and NM-Co Border
Georgia - Spikes near Rome (KCZL & KRMG)
Idaho - A few fixes around southern and central Idaho
Maryland - Corrections in and around Baltimore
Montana - Numerous fixes in Montana
--- Note that the 2 large spires are not correctable at Glacier Intl - KGPI (Asobo will have to fix) ---
Nebraska - Spikes on Missouri River (KOMA)
Nevada - Lakes near Elko-NV (KEKO)
New Hampshire - Numerous fixes around Concord (KCON)
New York City - Spikes and Lake Fixes near Teterboro (KTEB)
Virginia - Spikes near Roanoke (KROA)
Washington State (PNW) - Spikes near Darrington and some near Seattle