I use ES File Explorer (from the Play Store) to connect to the LAN. You will need to make your movies folder on your computer shared by "everyone" on your local/private network or homegroup.
When you navigate to a movie/video and tap on it in ES File Explorer, DicePlayer should be one of your options. Works on my HTC One.
Or, in DicePlayer itself, swipe to the right to get locations. Click on the + sign under SAMBA server and put in your computer's local network IP address. You can find this by opening a command prompt and typing in "ipconfig". It will show a list of IP information for your computer. The one you want to put into your SAMBA server is the IP address that says "IPv4 Address". Usually, it's 192.168.0.?, where the ? can be anything depending on how many devices are on your network.
You will need to unzip that and then place the libffmpeg.so file onto the root of your SD card.
Then in DicePlayer, go to settings and near the end you need to check the "Custom plugin" box, which will install that codec.