Slow conversion, high RAM usage

Add "MC to FCE.exe" to your antivirus program's exception list. The converter does a very large number of reads and writes to your drive at a very high rate. AV programs often will scan every write to the drive, causing a massive drop in speed and causing data to quickly queue up for writing, increasing RAM usage.

An SSD will improve performance significantly over traditional hard drive.

Segments could not be fixed

Caused by other programs accessing segment files during conversion. Ensure no other programs are accessing the files such as antivirus programs.