For a conventional HVAC system, the RC-2000 supports 2-stage heat and 2-stage AC.
From page 1 of the RC-2000 installation instructions:
- Single Stage Heat/Cool Conventional
- Two Stage Conventional (2 Stage Heat / 2 Stage Cool)
- Heat Pump and Geothermal Heat Pump (2 Stage Heat / 1 Stage Cool)
- Two Speed Heat Pump and Geothermal Two Speed Heat Pump (3 Stage Heat / 2 Stage Cool)
- Dual Fuel Heat Pump and Geothermal Dual Fuel Heat Pump
- Humidifier and Dehumidifier Control
On page 19 of the installation instructions for the RC-2000, it tells how to change the stage settings. The RC-1000 is a cheaper model which only controls single stage heat and cool.
The settings for the HZ322 are explained on page 7 of that installation manual. It can control 2 stage heat and/or 2 stage AC. The settings for 2-stage control are in the section labeled: Stage 2 Control. Options are: Timer, % Zones, Off.
Cate 5e is fine for the panel to thermostat connections.
Since you have multi-zones and multi-stages, there is no predefinied way to connect it. You can use the multi-stage control on each thermostat to control the multi-stage of the HVAC unit, or the HZ322 has other options which don't even require a 2-stage thermostat. You may especially want to look at the "% Zones" option. This uses stage 1 when only 1 stage is on, but stage 2 when 2 stages are on. Its very bad to ever run your HVAC in stage 2 if only one zone is on. Its too much are air forced through one zone.