The following works for me:
B:= 1.417313842*Q^(5/6)*hypergeom([-5/2,1/2], [-3/2], .9779060952/Q^(1/3));
plot(B, Q= 1..5);

The next point is:

memory used=89.25MiB, alloc change=0 bytes, cpu time=2.18m, real time=2.18m, gc time=171.88ms
2.5    .1305720815

The point after that took even longer, and I didn't have the patience to wait for it. One weird thing about the last point computed: The garbage-collection time was substantially less than the other points, even though the overall time was substantially longer.

@vv Brilliant technique. Vote up. But I'd like to know how you chose n and nx. And why a polynomial rather than a rational function? I haven't been able to change any of those and get anywhere near your infnorm.

Your exp(xt) should be exp(x*t). That being said, there's no direct way to solve integro-differential equations in Maple. Someone may be able to come up with a ad hoc method.

@tomleslie These are ODEs, not PDEs, so Maple's dsolve can determine the value of omega by the inclusion of one more boundary condition. For this purpose, it's better to use omega in the equation in place of omega^2, and then to take the square root of the resulting value.

@taro Personally, I don't like the new toolbar. They've completely removed the use of red, which makes the icons harder to find. There are only two colors in the new toolbar: grey and blue. At the very least, the stop sign should be red!

@Henk Although evalf gives a somewhat meaningful result in your example, the more-usual way to convert Sum to sum is the value command:

Sum(2^j, j= 0..9):  % = value(%);

This uses exact computation rather than numeric approximation.

@tomleslie Using Maple 2016.1 with Digits = 15, I get

                 [1, 1] = 2.04426478581227e40
                 [1, 2] = 2.04426478581227e40
                [1, 3] = -2.04426478581227e39 
                   [2, 1] = -Float(infinity)
                    [2, 2] = Float(infinity)
                    [2, 3] = Float(infinity)
                    [3, 1] = Float(infinity)
                    [3, 2] = Float(infinity)
             [3, 3] = Float(infinity)*omega[1, 1]^2

If I use Digits = 10, then I get what you got. A much higher setting of Digits is required. There was little change between 50 and 100 Digits, so I trust those results more.

@mmcdara Your restart is still not in its own execution group. The problems that can be caused by this are somewhat unpredictable, and I have a suspicion that this has some role in the strangeness that you are experiencing. To put it in its own execution group, enter restart; at a prompt, and hit the Enter key (or Return key). Then enter your other commads.

@candy898 

When you have m^n, it tries to use the procedure `^` recursively, but what you want is to fall back to the original `^`. To do that, change m^n to `:-^`(m,n).

@candy898 You should follow Joe's advice. Put the entire code of the module, and all of its procedures, into a single plaintext file, which you'd load with the read command, followed by with.

However, it's another issue that's causing your sortcollect problem. In the return statement of procedure M, you have an extra space after sortcollect. This extra space would make no difference in a plaintext file. But since you're using 2D input, the extra space becomes a multiplication operator. This operator is plainly visible in the code that you copy-and-pasted directly above.

@candy898 

You need to have

option package;

in the module, and

with(Q);

before you use the module.

All you've shown is a lot of code that apparently works. We need a negative example. Please post a worksheet showing something not working. Point out explicitly in a comment where it is wrong and what you expected to get instead.

I reduced your upper for loop limits from 20 to 5, just so that I could get somewhere with this computation. The huge exponents of the coefficients of the resulting polynomials and the mixture of positive and negative terms indicate that the expression has no numerical significance.

So, time to rethink this whole operation. What exactly are you trying to do?

@acer Here's why I said that something must've changed with respect to Matrix (rtable) evaluation:

I took the worksheet that the OP posted in their first response to VV's answer. (This worksheet is named Forum_Question_V2.mw.) I loaded it into Maple 2016 without changing anything, and I "executed entire worksheet." It worked in the sense that I got a fully evaluated numeric Matrix. Then I did the exact same thing in Maple 16, and it didn't work: the result of the two-argument eval was a symbolic Matrix.

Now, if the issue is how the Matrix is entered (using palettes, using unevaluation quotes, etc.), that would be the same in both of my cases above, right?