It seems that you are having some issues with your Slingbox SOLO since you cannot locate it on your network.
Most of the times, this issue is related to the security software running on your computer. If the Slingbox shows solid lights it means that it is a "healthy" unit. In this case, I recommend you to check this link:
You can also connect the Slingbox directly into your router. This specific step will indicate if the issue is related to the TP-Link repeater.
Finally, you can also use a second computer and see how the Slingbox behaves on the same scenario but in a different computer.
Hope this helps.