The most features/functions/fixes for Solo APs will be in the latest version available.
I just zipped up all the supported Solo AP version 188.8.131.52.1347 code to the Support Portal:
Read the Release Notes
, and find the firmware download file here:
Supported AP models are: H500, H510 (build .1350), R300, R310, R500, R510, R600, R700, R710,
T300, T300e/n/s, T710, T710s, 7055, 7352, 7372, 7782, 7982.
Note: Some Solo AP users might like 104 for your ZoneFlex 7055/7372/7982/7782 Legacy APs!