Are the scenes identical that your rendering?
Are you exporting your scene to the standalone or using the 3ds max integrated plugin?
Have you checked out the manuals?http://render.otoy.com/manuals/Standalonehttp://render.otoy.com/manuals/3dsMax
It could be that your rendering with a different kernel or if you are using an HDRI when you were not before, the HDRI could be troublesome or importance sampling is not on or something like that.
Try the hotpixel_removal in the imager (once we sort out why the settings are not taking effect). Also quite often "hot pixels" are actually caustics so try increasing the caustic blur to see if that makes a difference (smooths them out).