This is a very demanding game for a RPG Maker game when it comes to the hardware. It's not just the MZ3D, but there are things like the day/night cycle which uses lots of resources hardware wise. I wouldn't recommend using laptop unless it's a gaming laptop with at least gtx 1060. If the fps is that low in the town already, it will be much worse once you leave the town.
I don't have any problems with the mouse on my end, but my specs are Ryzen 2600x, RTX 2070 and 16gb ram. Unfortunately, I don't think it's even possible to optimize this game to run on laptops that are not meant for gaming. This is a much more ambitious game than most RPG Maker games and I thought I had put the minimum system requirements to the description, but it seems that I had forgotten (I've now added them).
If you have more powerful laptops, I'd suggest trying them out as there simply is no way I can get this to run properly with those specs you provided - unless I redesign the whole game and split every area of the game in many parts, ditch the day/night cycle etc, which I'm not going to do. There probably will be some optimization along the development and I learn new tricks from time to time, but this has been developed with desktop setups in mind from the beginning as the MZ3D doesn't perform well on mobile platforms.
If you are willing to test it with those other laptops, I'd be interested to know their specs and how the game performs on them.
Thanks for the feedback, I appreciate it!
EDIT: I forgot to mention, that I'd be interested to test your mouse plugin and see if it makes any difference. I've also made some optimization to the day/night cycle in the past few days, but the results so far are not that promising.