Cannot use yii\db\Schema as Schema because the name is already in use

[patschwork]

What steps will reproduce the problem?

After creating a schema (http://frontend.dev/index.php?r=builder) the error occurs when trying to create an entity

Additional info

PHP Fatal error: Cannot use yii\db\Schema as Schema because the name is already in use in D:\DEV\yii2\vendor\tunecino\yii2-schema-builder\models\Attribute.php on line 6

This was a fresh "installation". I updated Yii2* and dependencies to most current stable versions without getting rid of this error.
When the "use Schema" is commented the next error occurs at the TYPES...

Q	A
Yii vesion	2.0.15.1
PHP version	PHP 5.6.3 (cli) (built: Nov 12 2014 17:18:08)
Operating system	Windows 10