Go careful if using domestic silicone sealant, it might look the same but some develop grease marks over time. Craft silicon might be more expensive but it's worth it.
One of the new products we have over here is a clear glue gel from Pinflair, acts like silicone giving the height but stays clear and hasnt got that awful smell.
If you're struggling to get either glue in the US
www.joannasheen.co.uk sells them and it's free p&p with a �5 minimum spend.