Hi @cruss ,
First of all, let me know if the instructions below are not clear enough, or if you need some additional help with other steps in your flow.
I ran some tests here and actually you can capture the priority from the both triggers ("When a new task is created" and "When a task is assigned to me"). The priority is measured in a numeric range from 0 to 10, in a descendent order of relevance, being 0/1 for "Urgent", 2/3/4 for "Important", and so on.
Although there is no dynamic content to access the "priority" from the trigger, you can refer to it by using the expression triggerBody()['priority'], just like in the image below:

Here is a new task just added to the planner (with an "important" priority):

And here is the output of the triggerBody()['priority'], capturing it as 1:

So you can use this numeric range inside a condition in your flow, creating the event only for those tasks that have a priority lower or equal to 4.
If you are new to expressions in Power Automate, the last section of this article that I wrote some months ago has some instructions about how to use it: http://digitalmill.net/2023/07/31/using-dynamic-content-in-power-automate/
Let me know if it works for you or if you need any additional help!
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