Does your light turn on if you set only the intensity and don't add "turn on"? That might be worth a try in case it's considering itself already on and doesn't respond to being told to turn on again. Or use the full Rule machine and split out the commands. Actually try them in RM anyway, it just might work better.
I stopped using Simple Rules some time ago, I remember I wasn't totally happy with it but I don't remember exactly why now, cos I am using Basic Rules quite happily for the simpler rules, so it wasn't that it just had limited functions
Have a look at the following post for a similar use case. I would personally use Basic Rules for this, with time constrain (restrictions) for the motion activated lights between two times:
You'll need them split into two separate rules like you had them in Simple Automation Rules. Do you want the motion trigger to work any time of day or just between the times the for the timed light on?
I would make use of the "modes" for night times and restrict the rules based on those. So for example. I commonly use longer motion inactive times for evening and brighter lights, and shorter time-outs and dimmer lights at night. Check this video for more details:
Don't rush into Rule Machine. Familiarize yourself with everything else, and when you harvested the power of your hub and you are ready for the phase 2.0 of your automated home, then look into enhancing your automations with Rule Machine. I have very few Rule Machine rules. Most of my rules are done in Basic Rules app. I use Rule Machine for things that no other app can do.
We have recently changed the interface and the videos have not been updated yet. The Location page has been removed and fields have been merged into Hub Details page. Sorry about that.
That is true (steep learning curve), but any robust HA system out there today is... I think you'll find it improves quickly -- as you play around, you get used to the "ism's" and your fluency goes up fast. Unfortunately, there's no way to really shortcut that -- you just need to dive and get your hands dirty, and that can be tough at the very beginning.
But stick with it and ask lots of questions here! I still learn new stuff all the time here from other peoples' questions.
Good call on starting in Basic Rules - that's intended to be an easier starting point. Many folks here still do most or all of their rule-based automations in BR.
I was really intimidated by Rule Machine at first, but once I got comfortable with Basic Rules and Hubitat overall, I started playing around with RM. It is a crazy powerful rule engine, so it can open up a lot of doors once you're ready. But probably no need to dive head-first into RM at this point -- then the overall learning curve could get pretty overwhelming!