Theme installation problem, please help!

Hello, I am installing this theme, Basecart for my OC V2.3.0.2
https://www.opencart.com/index.php?rout ... =47&page=2

Here is the error I got:
Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 22Notice: Undefined variable: theme in /home/coltterc/public_html/xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 24Notice: Undefined variable: theme in /home/coltterc/public_html/xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 26Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 28Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 30Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 32Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 34Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 36Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 38Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 40Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 42Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 44Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 46Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 48Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 50Notice: Undefined variable: theme in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 52
Notice: Undefined variable: nav in /home/coltterc/public_html//xxxxx.com/catalog/view/theme/basecart/template/common/header.tpl on line 79

Please help me, thank you in advance!

You'll need to get in contact with the BaseCart Theme Supplier, no-one else
would be able to know, I assume...
Ernie