OJS 3.1.2. Problems with CostumeBlock Plugin

Hello,

I have some problems after Upgrading OJS for 3.1.1.-4 to 3.1.2 with the CostumeBlock Plugin. I have PHP 7.2. and driver MySQLi. I can’t manage the Costumes Blocks anymore. In the same time, my PHP-Log give me this errors back:

PHP Warning: Declaration of DRIVERDAO::setOAI(&$oai) should be compatible with PKPOAIDAO::setOAI($oai) in /www/htdocs/w018207c/OJS2/plugins/generic/driver/DRIVERDAO.inc.php on line 19
[08-May-2019 15:36:51 Europe/Berlin] PHP Warning: Declaration of CustomBlockPlugin::getBlockContext() should be compatible with BlockPlugin::getBlockContext($contextId = NULL) in /www/htdocs/w018207c/OJS2/plugins/generic/customBlockManager/CustomBlockPlugin.inc.php on line 134

Could one help me?

Best regards,
Felix