Hi Dale Claxton,
Yes, icmp error inspection is supported in version 9.3 on device running in Transparent mode. For unsupported features in Transparent mode are in the following link. Go to Table 5-1 Unsupported Features in Transparent Mode.
http://www.cisco.com/c/en/us/td/docs/security/asa/asa93/configuration/general/asa-general-cli/intro-fw.html#76977
Spooster IT Services Team