Partial Answer
David Spence,
I gave it a shot, and got a partial answer with two defects.
First of all, I assume you're trying to define a betting strategy for use with CVData, so that you can simulate the strategy.
Start CVData and enter the correct information on the screens for Setup, Rules, and Playing Strategy. Then click the Betting Strategy icon. Set the Unit Size to 5 (for $5 units, since that's the greatest common multiple for your bets), then click the Define/Edit Strategies button, which invokes the Betting Strategy Configurator.
Select Create a new Betting Strategy. In the Strategy Name box, type "Spence" (or some other name). In the folder list, open the Standard folder and select the 1-6 Spread, then click the Init button.
This will open the Basic Strategy Table window. Uncheck the "Reset after shuffle" box (this will ensure that your first bet of the shoe will be the same as the last bet of the previous shoe). On the Count Range spinners, set the Start value to 0 and the End value to 4. In the Standard Bet Table box, enter the following values under the Units column (leave the Hands column set to 1): 3, 5, 10, 20, 25. These values corespond to the number of nickels you'll bet, so they represent bets of $15, $25, $50, $100, and $125. Check the boxes for No increase after a loss, No decrease after a win, and No large increases.
Now comes the fun part! Click the Advanced icon to open the Advanced Strategy Table. As you can see there, if your previous bet was 10 units ($50), after a win you'll bet 10 units for any TC<=+2 and 20 units for any TC>=+3. Thus, if you won your previous bet, your new bet will always be at least equal to your previous bet, but will never jump more than one row on the Units bet table. This is one reason why my answer is labeled "partial": it doesn't allow for huge increases after a split (or double down) with two wins. For example, if your previous initial bet was 5 units and you split once and won both, now you've got 20 units sitting in the betting circle. If the TC jumped to +4, your strategy would allow you to bet all 20 units (you said you wouldn't "go into the rack" to make it 25 units). However, according to the Table, your next bet will only be 10 units, since the program doesn't appear to allow the user to account for the split win.
Now you're wondering how to account for the larger than $125 bets... here's how to modify the table! Say your previous bet was 25 units, you won it, and the new TC is above +4. According to what you wrote, now you want to bet $150 (30 units). On the table, look under the Last Bet column for the "25" entry. Now move to the right and locate the row labeled "Won" under Last Hand. Go all the way to the right-hand column of the table, under TC>=4, and change the "25" to "30". This will cause the program to add a new row to the bottom of the table corresponding to a Last Bet of 30. On the "Won" line after the 30, enter these values: 30, 30, 30, 30, 35 (this will cause the program to add yet another line, for a last bet of 35). On the "Lost" line enter these values: 3, 5, 10, 20, 25. What these entries represent is this: if you won the "30" bet, your next bet will be either 30 again or, if the TC>=+4, 35 units; if you lost the "30" bet, your next bet will correspond to the TC. Now for the "35" row, on the "Won" line enter 35, 35, 35, 35, 40; on the "Lost" line enter 3, 5, 10, 20, 25.
Continue in a similar fashion for the "40" line and then the "45" line. When you get to the "50" line, just enter all 50's on the Won line: don't enter "55" for Won, TC>=+4. This is the other reason why my answer is "partial": you have to decide in advance what your maximum bet will be. I stopped at 50 units because I got tired!
Finally, click the Exit button. The program will ask you to select a betting strategy: select the one you've just created. Finally, run the sim.
I tried this out and found that, you one player heads-up in a 6D game with 5/6 pen, your average hand 1 bet for each shoe will be about 6.455 units (a bit over $32). Also, out of a total of 50 million rounds, you'll place about 22,000 50-unit bets (but you'll have a commanding 4.16% advantage on them.
Hope this helps!
Dog Hand