My TurboCAD default is Inches, but every DWG file I have opened gets interpreted as mm (millimeters), so the Scale is off by 25.4 (the inverse of 0.03937...).
My solution is to bring up the Options / Space Units pop-up menu, select Metric, make sure that the Convert units after alteration radio button is NOT checked (e.g. empty) and then press OK.
I then immediately bring back the Options / Space Units pop-up menu, select English, and THIS TIME MAKING SURE that the Convert units after alteration radio button IS checked and then OK.
TC Pro Platinum 2020, 2019, 2018, 2017, 2016 & 2015 (all with LightWorks & RedSDK) & V21
System: i7-5820K @ 3.30GHz, ASRock X99 Extreme4, 16GB DDR4-2133 RAM, Gigabyte GTX 970, Samsung NVMe SSD 950 (256GB), Windows 7 Pro (64-bit) SP1