Sorry this is late, I live in a rural area where internet bandwidth is excruciatingly slow and even sending a message is a challenge at times.
And as much I'd like to help, I don't know how to. Maybe this is a case of hardware issue such phone not being to handle RPGM VX, as it is very very much more resource intensive than compared to the previous RPGM engines. Particularly a phone's GPU and CPU is usually what falls shorts and therefore it lags.
My phone on the other hand had the issue with GPU and for the most likely reason as to as why it really, really lags with the flashing spots on a map is probably because [capture1], the game dev, had never intended this to be played on a mobile emulator therefore slacked in coding optimization in running this on a device that isn't strong as your average computer.
Oh and I have to say this before anyone just go and oversimplify as "get more GPU ggezez":
This GPU/CPU issue is more of an idea, less of a fact, as I had not been able to properly measure the usage of my phone's hardware to objectively measure and collect evidence as Android above 8 is getting tighter and tighter with "who's program and what program" gets a phone's hardware information to where it is used and how much is available. I had tried other apps, but Samsung's a bitch and so is Android 11. Rooting is not my specialty. And I am not a betting man that I am capable and knowledgeable enough to avoid bricking my phone if I so attempt to do so.
There, I guess. For at the end of it, I can only wish you luck and try finding ways yourself.