score:2
COK is a very small airport, so assuming no delays, the connection may work out (wouldn't expect the bags to make it though, so keep essentials in cabin bags). The fact that your final airline destination is GOA, not BLR, would add complexity/delay to getting your bags sent-on. In terms of flying within India and officious customs etc. it's not has bad as it used to be (I've travelled in India about a dozen times). I was in Kochi, Mumbai and Delhi last week. We didn't have super high-end stuff, but had 4 tablets, expensive headphones (which didn't survive the 300 ohms outputted by Air India's Dreamliner), digital SLR, smartphones, headphone amps a Microsoft Surface i7 etc. No-one batted an eyelid at any of it. Obviously you will face different customs officials, but in general Indians carry a lot of high-tech gear these days now (especially via BLR), so I wouldn't be super concerned. Download any receipts from eBay/Amazon if you can - or check your inbox. Or take a date-stamped photo of stuff.