There is a way to embed your channel on your blog with a specific video playing first (instead of the first video in your channel), here are the exact steps:
1. While your ShortForm channel is playing on the Watch page at www.shortform.com/watch, click on the "Embed" button, and copy the embed code for your channel into a text application.
2. Go back to the Watch page, click on the thumbnail of the video in your channel that you want to start playing first in the widget, and copy the shortened URL of the video (shrt.fm/xxxxxx) under the "Share with Friends" section on the left-hand side of the page.
3. Paste the shortened URL into your browser's address bar, and press "Enter" on the keyboard. The original longform URL of the video (www.shortform.com/UserName/ChannelName/VideoName) will appear in your address bar. Copy the "/VideoName" part of the longform URL.
4. Paste the "/VideoName" into the embed code that you copied into the text application, between the "/ChannelName" and the "?". This altered embed code will play that specific video first in the widget. Copy that embed code into your Tumblr/Blogger/Typepad account and you're done!