@User: You can just change the LEF version from 5.5 to 5.7 in the file. The only thing incompatible that I am aware of is that if there is a "SOURCE" line, it needs to be removed as it was deprecated in 5.6. Then you can use "CORE WELLTAP". But the underlying problem here is that SkyWater did not provide LEF files for some of the cells like the tap cells, and Magic has no obvious way of knowing that the cell is either a CORE cell or a CORE WELLTAP cell. It would have to be done (@User) in the script that prepares the LEF files from magic, which would need some additional handling to note that the cell name is "tap" and in response to that issue the command "property LEFclass {CORE WELLTAP}".