Confused about ESPurna, Tasmota MQTT and Tasmota Integration

Configuration
1

Hello specialists,
I’m confused about how HA handles the different integrations. I had some Arilux LC-06 (btw. RGBCW) running with ESPurna and so far they worked well. But I decided to switch all my devices to Tasmota so too for the LC-06. I use the ‘EvTheFuture/dim_lights_based_on_sun_elevation.yaml’ blueprint for dimming.
For watching the BP I’ve defined a brightness sensor:

  - platform: mqtt
    state_topic: "homeassistant/lieschen_status/brightness/set" #something like this
    name: "lieschen_status_helligkeit"
    unit_of_measurement: 'degrees'

Now switched to Tasmota:
1. the blueprint doesn’t work with the Tasmota Integration. Didn’t find something like above i.e.

 - plattform: tasmota
   state_topic: .....Dimmer... ???? # how to define a sensor for the dimmer value???

Nevertheless I switched to MQTT Integration (with SetOption19 ON) so this works:

  - platform: mqtt
    state_topic: "garten/cmnd/lieschen_statusled/Dimmer"
    name: "lieschen_status_helligkeit"
    unit_of_measurement: 'degrees'

(I use ‘degrees’ to show a history-graph in conjunction with ‘sun.elevation’) (helligkeit=brightness)
The BP now works.

2. Now I can’t change the color via the UI,( ON/OFF, brightness is fine) the color stays like bevor.
An automation which changes the color works. :confused:

3. Also rgbww_color doesn’t work while 'rgb_color: does. This is with Tasmota & ESPurna

Any hints? Mainly why changing the color via UI doesn’t work.
THANKS