Hi Michail,
It will be easier for the community to answer your queries if you attach the model to try it. Creating a model from the picture would be time consuming.
For the first query, did you set the sample time of the system appropriately. make sure that it is discrete enough(atleast 100 msec) so that the stateflow transition happens as expected.
For the second query instead of using a "event" to trigger a transition. Try using the "rising" function in stateflow to detect edge rises.
Also, you should try making your chart a little more clear and try to add another state as below:
The above one works for me and produces the expected output. Here, 'reset' is the reset signal directly fed to the stateflow chart.
To know more about the "rising" function, refer to the following documentation:
Hope this Helps!