Edited map issues - or the game crashing when uploading a map - could be due to many different reasons. Namely:

• Your Steam account cannot be limited. Read more here;
• You have to accept the latest Workshop EULA here;
• You can hit the per-player upload limit in case you have already submitted tons of maps;
• The map you are trying to upload has some issues with its files (no preview, bad description, bad naming, or such);
• Firewall settings or internet connection issues. A player in the past has mentioned that white-listing the IP helped him solve it, too (Steam FAQ);
• First, backup and then delete the folder %UserProfile%\AppData\LocalLow\Hologryph\Secret Neighbour\MapsLocalStorage\. This is where the editor saves all your maps;
• Delete %UserProfile%\AppData\LocalLow\Hologryph\Secret Neighbour\SecretNeighbor.es3; this is your player settings file, so after doing so, the game will launch using the defaults.