Problem with template option in Shop App page functions

I came across a problem while attempting to pass in custom templates in the new Shop App (gamma 1).

Per the documentation, displaying a product like this works fine: perch_shop_product('my-product');

I know that the default template is shop/products/product.html. When I edit product.html my edits come through properly.

However...

If I try to display a product using these functions, I get no output at all:

perch_shop_product('my-product', [ 'template' => 'product.html' ]);

perch_shop_product('my-product', [ 'template' => 'my-template.html' ]);

Any time I use the template option, I get nothing. Other options, such as count work properly. I'm getting the same result using perch_shop_products(); where the default template is list.html. I've copied over the template files in the shop download to my templates folder as per usual...

Many thanks!

Time    Δ   Debug Message
0.0189  0   SELECT u.*, r.* FROM perch2_users u, perch2_user_roles r WHERE u.roleID=r.roleID AND u.userEnabled=1 AND u.userID=1 AND u.userHash='5185b59ed90ba3360d076e3bcab1c5e0' LIMIT 1
0.0195  0.0006  UPDATE perch2_users SET userHash='d0f30f61b5e8cb44ad41c567475a13b3' WHERE userID='1'
0.0198  0.0003  SELECT p.privKey FROM perch2_user_privileges p
0.0216  0.0019  SELECT * FROM (SELECT DISTINCT settingID, settingValue FROM perch2_settings WHERE userID=1 OR userID=0 ORDER BY userID DESC) AS settings GROUP BY settingID
0.0581  0.0365  SELECT * FROM perch2_shop_products WHERE productID='1' LIMIT 1
0.0668  0.0087  Using template: /templates/shop/products/product.html
0.084   0.0172  SELECT productID, productVariantDesc, stock_level FROM perch2_shop_products WHERE parentID=1 AND productDeleted IS NULL ORDER BY productOrder ASC
0.0986  0.0147  SELECT * FROM perch2_shop_brands ORDER BY brandTitle ASC
0.1008  0.0022  SELECT * FROM perch2_categories c, perch2_category_sets s WHERE c.setID=s.setID AND s.setSlug='products' ORDER BY catTreePosition ASC
0.1043  0.0035  SELECT * FROM perch2_shop_currencies WHERE currencyActive=1 ORDER BY currencyID=142 DESC, currencyCode
0.1058  0.0016  SELECT * FROM perch2_shop_currencies WHERE currencyActive=1 ORDER BY currencyID=142 DESC, currencyCode
0.1072  0.0014  SELECT * FROM perch2_shop_currencies WHERE currencyActive=1 ORDER BY currencyID=142 DESC, currencyCode
0.1086  0.0014  SELECT * FROM perch2_shop_tax_groups ORDER BY groupTitle ASC
0.114   0.0054  Queries: 13
0.1141  0.0001  Memory: 4.2141