3.1 Update Laggs and Issues

Hello D5 Render Team,

First of all, thank you for the continuous development of D5 Render. I’ve been using it professionally for a long time, and after updating to version 3.1, I’ve unfortunately encountered several serious issues that directly affect my workflow.

Most of these problems only started after updating from the previous version. Before 3.1, the same projects worked smoothly on the same hardware.

Here are the main issues I’ve experienced:

Heavy projects created in previous D5 versions no longer open correctly. One of my larger scenes freezes immediately after opening, the screen turns gray, and D5 crashes after about 20 seconds.
Other heavy scenes still open but have become extremely slow. Camera navigation, viewport movement, and general interaction are significantly less responsive than before the update.
Materials using True Displacement created in D5 3.0 are no longer displayed correctly in 3.1. They can usually be fixed manually by adjusting settings, but every material has to be edited individually, which becomes time-consuming.
Saved camera views occasionally lose their focal length settings. For example, I may save multiple views using different focal lengths (25mm, 35mm, 60mm, etc.), but after reopening the project all cameras are reset to the same lens value, while all other settings (lighting, sun position, exposure, etc.) remain unchanged.

One of my biggest concerns is that I also create and sell professional D5 scenes. Some of these scenes were created several months ago in previous versions of D5. After updating to 3.1, some of these files no longer open correctly. This means I can no longer guarantee that customers purchasing my scenes will be able to open and use them successfully in the latest version of D5.

I also noticed on the community forum that other users are experiencing similar problems with older, heavier projects after updating to 3.1, so it doesn’t seem to be an isolated case.

My workstation has not changed, and these issues did not exist before updating to version 3.1. The overall performance and stability of older projects have noticeably decreased.

Could you please let me know if these issues are already known, whether they are being investigated, and if there are any recommended solutions or upcoming fixes? I would really appreciate any feedback, as these problems are currently affecting both my commercial work and the projects I provide to my customers.

Thank you very much for your time and support.