Layton Stewart's 22nd-minute penalty opened the scoring in Belgium before Curtis Jones doubled the advantage for Barry Lewtas' side midway through the second half.
The result maintains the young Reds' spot at the top of Group E, having now recorded two wins and a draw at the halfway stage.
Stopper Jakub Ojrzynski produced a good save low down to his right within the opening eight minutes to keep out Xander Lambrix's drilled long-range effort.
That intervention was crucial as the visitors took the lead midway through the first half. Stewart chased down Leighton Clarkson's crossfield pass and was adjudged to have been brought down by goalkeeper Maarten Vandervoordt.