Dimmer Rule Between Scenes - Seeking Assistance

I’m currently working on setting up a smart home system using OpenHAB with IKEA Tradfri devices. I’ve created several scenes for different times of the day, such as evening and dinner. Each scene adjusts the brightness of various lights in the house. However, I’m trying to add a feature where the lights transition smoothly from one scene to another over a period of time, like dimming from 30% to 60% over 45 minutes. I found a rule example that seems to fit my needs, but I’m stuck on how to set the starting value correctly. I’ve tried modifying the rule, but it doesn’t work as expected. Could someone guide me on how to properly implement this transition? I’d really appreciate any advice or suggestions to help me get this working smoothly. Thanks in advance!