3.0.1 Install problem : still running... site down : error in front-end

Hello,

Previously ES last 2.9 was working well

Yesterday :
I have tried to install new 3.0.1 and stay stacked in install process :
arrived at the end of the process without errors...
then when i clic to "Lauch Backend", the install process is starting again, and again...

I have re-downloaded "com_easysocial_launcher_pro_3.0.1_joomla.zip" tried again, but same result

front-end site is down
ERREUR: 0
Call to a member function getType() on null


Today :
New tried and i am able to succeed the install
can access to ES backend (some icon are missing) seems working

but still
front-end site is down
ERREUR: 0
Call to a member function getType() on null



Can you help please ?
Thanks in advance
Loïc