Have same problem. Version:4.1.70.26806
Recently upgraded to ...did not use Dyn Reg. Module before this..DotNetNuke Version: 6.1.5.
Have tried all browsers, clear cache, restart, upgrade Java. DNN Manage Button not active.
Also,
On some pages with DS Module ,Manage Button displays sub-menu (settings, import etc.) but will not enable those actions. Tries "Javascript DNNmodal.show...... (see att screen shot _error#2.png)
Tried re-installing Module as well. Still not working?
BTW, also using Dyn. Forms and this module supports the DNN Manage module settings?