A quick note about IC2 power tiers: there are several levels/tiers of IC2 power, often with their own associated machines and energy storage blocks. Supplying power of a higher tier to a lower tier device will blow it up, and using the wrong cable will destroy it (if all machines on the cable are able to accept the packet the cable will just disappear, not explode). The main tiers for machines are 32 EU/packet for batboxes and your basic machines (e.g. macerator, compressor, electric furnace etc, copper cable), 128 EU/packet for MFEs and induction furnaces (probably others as well, uses gold cable), 512 EU/packet for MFSUs and mass fabricators (and possibly others, uses glass fibre or HV cable), and finally 2048 EU/packet, which is only really involved in high output reactors and certain power transmission setups, and requires HV cable. Use the lowest cable suitable for your power transmission requirements, as at a given packet size bigger cables are lossier (although larger packets on larger cables are generally less lossy), unless you feel like investing in glass fibre cable, which is very low loss. Certain power generators (e.g. solar panels, water/wind mills) use very low power, and can be wired to energy storage through tin cable (which can't even carry 32 EU/packet).
EU/packet represents the size of a pulse of energy. An energy storage will emit at most one pulse per tick, so batboxes emit 32 EU/tick, however transformers accept 1 packet/tick, so a fully powered LV transformer can provide up to 4 packets per tick, potentially providing 128 EU/tick at LV. The important point is that EU/tick is important to determine how much power to make available and how (e.g. how many parallel storage devices, potentially using higher power tiers and then transforming or upgrading) whereas EU/packet tells you if your setup will explode.
IC2 energy storage blocks (including your MFE) have a face with a dot on them (I don't know about your texture pack, but there should be 1 face with some sort of mark) that will emit power at the tier of the storage into an attached wire, while all other sides will receive power from other sources. Note that you should never have any link between the output (dot) face of the energy storage and the input faces as the energy storage will repeatedly send power to itself and bog down your computer/server.
On any IC2 transformer the 3 dot face is the higher voltage, and the name is the target voltage. For instance, the LV transformer puts out LV (32 EU/packet, the output of a batbox) from the 5 single dot faces when powered with MV (128 EU/packet, the output from your MFE). Transformers reverse when redstone is applied, accepting their lower voltage (LV for the LV transformer) into any of the 5 single dot faces and output MV from the 3 dot face. Right clicking one of the single dot faces of a transformer will rotate it so the 3 dot face will end up on the face you right clicked, while sneak right clicking (hold shift to sneak by default) will rotate the 3 dot face to the opposite side of the transformer to the face that you clicked.
You can power low tier machines from MV in one of 2 ways: either inserting transformer upgrades (1 per tier difference, eg to get to 512EU/packet on a 32EU/packet machine you will need 2 upgrades) into 1 of the 4 slots on the right side of the interface (the 4 off to the side that don't really seem to do anything), or by using a transformer as above. Note that if you go the upgrade route the last thing to do is connect your MFE to the rest of the wiring, as the machines must have the upgrade inserted before connection to MV. Also note that you must use a sufficient cable to convey higher tiers of IC2 power, which means gold cable or better between your MFE and transformer (or all the way if using upgrades). Note that higher tier machines (e.g. the induction furnace) will accept lower tiers of power, but you may require parallel sources to keep up with supply if you're burning a lot of power.
I hope that's not too difficult to follow, it might be a bit jumbled.
