I installed the plugin Tablepress....
Here are the steps I did...
-I uploaded the plugin "Tablepress" from my PC locally to the wp-admin plugins screen.
- From there I activated the plugin
- Once activated, I did not see any new top -level menus or sub menus.
-I double checked my server plugins directory and the folder was there for Tablepress.
- I then went to the Developer Mode admin screen and made sure this was view-able...and saved and refreshed my wp-admin...still no new plugin showing.
-I logged out as the "Developer" and logged in as the "Administrator", now I can see the new plugin...it has a top-level menu in wp-admin.
- I deleted the plugin "Developer Mode"...logged out of the administrator, them logged back in under my normal user name.
- I then reinstalled the "Developer Mode" plugin...claimed myself as "Developer"...and looked for the plugin Tablepress...now i can see Tablepress in my wp-admin....
This is the only plugin that has acted this way...I've a couple others since then, and all have worked....so everything is good now!
Big thanks for this plugin and generous follow-up support!