Hello there. i have again same problem. i worked for project (Sketchup - D5 render) after some days when i opened project, it is empty from Sketchup models, i see only D5 ssets and can not restore it.
can help?
Hi georgemelkadze, can you take a screenshot to better understand
Hi mate, can you tell me the version of your Sketchup, D5, and converter, Did you update one of them recently?
- Also, please choose “Select file” after updating the livesync for Sketchup because it will not automatically recognize the connection to your old files after installation. The texture of the newly created save file will be lost by default if you choose “OK”.
D5 LiveSync for SketchUp - Workflow / SketchUp - D5 RENDER FORUM
- Did you use any cloud or server to save your work? Did it corrupt before saving it?
You can also check the historical version to find the model back.
If you think the things I mention above don’t have problems, it’s probably a bug, please send the logs, model, or scene to us for troubleshooting.
support@d5techs.com
How to collect log files:
D5 Support Tool - Get Help / Tech Support - D5 RENDER FORUM
Hello Bruce, thanks for replay. i dont know what is problem. it happens often with me. ic rated file (folder) with log file, D5 project file and Sketchup file, and sent it with Wetransfer. hope you will help me to restore it back with project and already done materials. 
LINK: WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free
Hi mate, please check your email, we sent you the file recovered. To confirm, did you save files in a network place or a local place? The model was imported using SketchUp, or directly into D5?
Hi Oliver, i got it on mail. Thanks so much.
Have not idea why it happens very often. I saved it on local yes, 
I open Sketchup model in D5 at first and then i use D5 converter
Hi mate, can we schedule a time for remote assistance, so we can check the environment of your devices and find the potential problems?