On Ruckus ZD and APs, changing the default VLAN from 1 to any other VLAN makes it tagged. As long as VLAN is configured as 1, it is Untagged. This is why connectivity is breaking when you setup the VLAN other than 1.
For the client connectivity issue, please confirm what VLAN(s) you are tagging on the WLAN? If you are tagging VLAN on WLAN's advanced settings, then make sure switch port connecting to ZD is configured as trunk with desired VLAN as Untagged (for ZD management) and rest of the VLANs as tagged.
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