I've a combination of standalone and lightweight installations on different sites. I'm using WCS for monitoring standalone AP's state. Before WCS version 188.8.131.52 (for example, in 184.108.40.206) it shows heatmaps for standalone AP's well, but now it fails with this error:
Error(s): You must correct the following error(s) before proceeding: Error:Object ''Device!172.24.64.200'' does not exist.
Make sure that use SNMPv2 when you add the autonomous APs to WCS. Also from the Monitor->Maps, choose the 'Properties' drown down and click 'Go'. On this page, set the 'Refresh from Network' to disable. By default this is always disabled.
Maps retrieve status and statistics information for APs from the WCS database where it is updated every 5 to 15 minutes. For debugging purpose sometimes its important to get latest data directly from device instead of WCS database. 'Refresh from Network' option is available for that purpose but it should be used cautiously and not turned 'ON' always.