I don't think you can make a vanilla abstraction, because it has an arbitrary number of outputs, and with abstractions, this is possible only with [zexy/initbang] as [loadbang] won't do it. If you're ok with a fixed number of outlets, I guess it's possible. Below is a screenshot of an abstraction I did with four outlets. For a dynamic number of outlets you would probably have to make an abstraction with the group of objects that repeats in the image below, and use [zexy/initbang] to make all the object/abstraction creations and connections in the main abstraction, but again, this won't be vanilla.

This information is included in the INSTALL.txt file that comes with the source, but it's not on the top of this document.

Maybe it has to do with the frequency you're sending the data. In the Max patch. [serial] is being polled every 100ms. Perhaps you have to reduce the frequency of your data. Other than that, [comport] can accept lists of values the way you do it, and these should be readable by the Arduino code.

Why are you reading the bytes from the serial buffer outside the if (Serial.available() > 0) test? Nothing is happening inside those curly brackets. All Serial.read() should happen within those curly brackets. Though, I guess the bytes will be available after the empty code snippet. Also, in the Pd patch you're using a fan out connection. Use [t b f] connected to every outlet of [route] that connects to a cold inlet of [pack].
As @ddw_music correctly pointed out, there's no [pack i i i i i]. What you need to do is change it to [pack f f f f f] but make sure you pass those values through an [i ] object before sending them to [pack].
Lastly, a better version of the code that reads the serial buffer is this:

int index = 0;
while (Serial.available()) {
  incoming[index] = Serial.read();
  index++;
  if (index > 4) index = 0;
}

Or something along these lines.

Can you share your patch, and the Arduino code?

Or use a [symbol] object and store the output of [openpanel] in its right inlet, if you don't want to use a GUI symbol box.

I guess it's better to do this in another language, like Python, which is great in handling text files. Perhaps the new [file] object included in the current test version of Pd will be better than [text], haven't tested it yet though.

How about this:

[0 1 2( [1 2 3(
|       /
|     /
[list split 2]
|
[unpack]
|      |
[== 0] [== 1]
|      |
[&&    ]
|
[sel 1] <- this will bang when the first value is 0 and the second is 1

You'll need to repeat the [== 0] [== 1] with [== 1] [== 2] and so on, for all possible lists, or something along these lines.

If you have lists, then you can use [list split 2] and unpack the first two values which you can then compare with [== ]. It's not very elegant, but it does what you want.

This thread is quite old, and AFAIK, @cuinjune has sort of rewrote the library and now there's only the [ofelia] external, and everything else is either written as a Lua script and loaded to [ofelia], or an abstraction, that includes [ofelia] with a Lua script loaded to it, pretty much the same thing, only the abstraction simplifies things a bit.
The best way to go would probably be to learn more about openFrameworks and Lua. This way you can really unleash the power of Ofelia!