NPM and extensions

I am completely new at a lot of this. Sorry if my question seems too basic.
How do I actually use these extensions in my Angular 4 project? gojs has been added to the project, I see the extensions in the gojs node modules.
I thought I could do
import * as go from ‘gojs’; in my component
and then use an extension such as go.TableLayout.

Next I tried import TableLayout from ‘…/…/node_modules/gojs/extensionsTS/TableLayout’; in my conponent
and new TableLayout() but I’m getting the following build errors:

ERROR in node_modules/gojs/extensionsTS/TableLayout.ts(414,8): error TS2403: Subsequent variable declarations must have the same type. Variable ‘child’ must be of type ‘Part’, but here has type ‘any’.
node_modules/gojs/extensionsTS/TableLayout.ts(445,8): error TS2403: Subsequent variable declarations must have the same type. Variable ‘child’ must be of type ‘Part’, but
here has type ‘any’.
node_modules/gojs/extensionsTS/TableLayout.ts(542,9): error TS2403: Subsequent variable declarations must have the same type. Variable ‘child’ must be of type ‘Part’, but
here has type ‘any’.
src/app/app.component.ts(3,8): error TS1192: Module ‘“D:/projects/gojs-app1/node_modules/gojs/extensionsTS/TableLayout”’ has no default export.

The first approach only loads the main go.js library.

The second approach is right, but one normally loads the JS file, not compile the TS file.

However all of the *.JS files in that directory were the result of compiling the *.TS files with the tsc --strict option so they should compile without warning or error. Maybe your compilation is not finding the go.d.ts file?