You can easily change the mouse theme by invoking lxappearance or through Mabox Control Center (which points to lxappeareance too). Yet, the option to change the pointer size is missing in the dialog. Not sure how difficult could be to include this feature in future versions of Mabox.
Currently a workaround is edit the ~/.Xresources file and (at the bottom) adding the line:
Values 48 and 64 are valid too according to your needs.
Similarly, Firefox is ignoring whatever mouse theme you choose and the pointer changes into another one when hovering the mouse inside it. The only solution so far is editing ~/.config/gtk-3.0/settings.ini file and commenting the gtk-cursor-theme-name line, ie, like this:
I was wondering if this can be fixed “under the hood” after the installation of Mabox.