Yes, GlockApps supports the testing mode via one dedicated email address.
To use the mode via one dedicated address, you need to create a sending account with your SMTP settings in GlockApps, generate a proxy address and send the message to the proxy address. GlockApps will do the rest for you: create a test and re-send the message to the seed list via your SMTP settings. The test will be created under Reports > Smart Tests in the Inbox Insight tool. This mode eliminates the need to create a test manually and copy-paste the id in the message.
Read more about email testing via one proxy email address.