The cool thing and the frustrating thing about Max is there are a million things you can do with it and almost that many different ways to do it. I've never needed the functionality that you need and are posting about here in this thread. And I don't fully understand why it has to be absolutely snapped to those faces instead of manually just getting it really close. But then again, I'm not working on your project and don't understand its intricacies. That doesn't mean it's not important.
I fully understand the personal perspective that the "most important" things in Max, are the things "I" need to do, and I do want it to do all the things I need, perfectly. Far too often, I have to resign myself to make up some workaround to get it to perform as I need it to.
But, you know all of this. You just need it to snap the way you need it to. I wish there was some way to get it to do so. I tried adding a point helper to a vertex at the corner of your planar selection and then snap to that helper, but that didn't work. There still may be some way to do it, I just don't have a good answer for you.
I'd go to the '3ds Max Ideas' forum and suggest it. If other users agree with you that is a feature that really needs to be implemented, then maybe the developers will put it on their list. You never know. In the meantime, you still need to get your work done sometimes we have to find a work around.
I'm sorry my idea didn't work for you. I hope someone else can come up with a good solution. I'll keep thinking about it and if I come up with something I'll jump back here.
Rob Holmes
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3ds Max (2023-2025), V-Ray 6.2, Ryzen 9 3950-X Processor, DDR 4 128MB, Gigabyte Aorus X570 Master motherboard, Sabrent Rocket NVMe 4.0 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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